POTATO

Study Name: IR-1 Potato General Study Comment: This represents various envrionments over several years data capture at the Potato Station.

METHOD: Both and Visual Examination CONDITIONS: Green House METHOD NARR: Collections made by D. Spooner and A. Contreras in region X of Chile in 1989 were maintained as root stocks and grown in a GH. Leaflets were collected andion of PVS, PVM, PVX, AMV, PYV and APLV. A survey of frn on Robinson Crusoe Island was done and insects infesting the plants were noted as possible virus transmission vectors. RESULTS NARR: A total of 47 clones of the Chion were tested. AMV and APLV were not found. Infection was detected as follows: PVS - 89%, PVM - 43%, PVX - 38% and PYV - 15%. On RC Island, plants were infested by Myzus persicae and Aulacorthum solani. PVS, PVM and PVX wer PYV were not. AUTHOR EXPLANATION: PVY is reported here for the first time as occuring outside of Peru.

Tubers were generated in a greenhouse in the winter. At harvest, one tuber from each of up to 15 plants was put in liquid nitrogen and then freeze dried. Freeze dried tubers were ground in a Wiley mill. 4 data points per accession based on two reads of each of two samples from the same dried tissue sample. A mean value of the reads was calculated.

Tubers were produced in three reps: 1) tuberlings grown in Kula, Maui, HI field; 2) seedlings grown in Kula, Maui, HI field; and 3) seedlings grown in greenhouse in Strugeon Bay, WI. Total AOA in tuber extracts was estimated using the DPPH (2,2-Diphenyl-1-pierylhydrzyl) method. Trolox was used as a standard, and total AOA was expressed as micrograms of Trolox equivalents per gram of tuber fresh weight. An average was calculated on the three tuber reps.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: Both and Visual Examination CONDITIONS: Green House METHOD NARR: Collections made by D. Spooner and A. Contreras in region X of Chile in 1989 were maintained as root stocks and grown in a GH. Leaflets were collected andion of PVS, PVM, PVX, AMV, PYV and APLV. A survey of frn on Robinson Crusoe Island was done and insects infesting the plants were noted as possible virus transmission vectors. RESULTS NARR: A total of 47 clones of the Chion were tested. AMV and APLV were not found. Infection was detected as follows: PVS - 89%, PVM - 43%, PVX - 38% and PYV - 15%. On RC Island, plants were infested by Myzus persicae and Aulacorthum solani. PVS, PVM and PVX wer PYV were not. AUTHOR EXPLANATION: PVY is reported here for the first time as occuring outside of Peru.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

Study Name: Resistance to Bacterial Stem Rot. Experiment Type: Greenhouse GREENHOUSE Study Year: 1987 Year started: 06/02/1987 Year ended: 02/05/1987 Comment: The plants were inoculated by crushing the leaf and petiole with tweezers and spraying with different levels of an ECC bacterial suspension. The accessions were given an index rating from 0 to 4 based on the resistance they showed.

Study Name: Resistance to Bacterial Stem Rot. Experiment Type: Greenhouse GREENHOUSE Study Year: 1987 Year started: 06/02/1987 Year ended: 02/05/1988. Three to four week old seedlings were inoculated by crushing the leaf and petiole with tweezers and spraying with five different concentrations of bacterial suspensions. The bacterial levels of E. carotovora subsp. carotovora were 105, 106, 107, 108, and 109. Plants were visually scored by a resistance index (0-4) and percentiles were based on the average of the five trials.

Study Name: Resistance to Bacterial Ring Rot. Experiment Type: Field FIELD Study Year: 1988 Year started: //1988 Year ended: 08/31/1990 Comment: The plants were inoculated by dipping the roots of each seedling into a mixture of C. sepedonicum. The plants were evaluated at four weeks and again at eight weeks and were given a symptom rating (0-5).

Study Name: Resistance to Bacterial Wilt. Experiment Type: Greenhouse GREENHOUSE Study Year: 1985 Year started: 12/31/1985 Year ended: 12/15/1986. Flats of three week old seedlings were not watered for three days and then inoculated by drenching each flat with 5 liters of 6.0 x 105 and 1.2 x 106 suspensions of P. solanacearum. A knife was thrust between the two rows to injure the roots. An adjusted survival percentage (-43.3-98.7) was given to each accession after a 21 day inoculation period.

Study Name: Resistance to Bacterial Ring Rot. Experiment Type: Greenhouse GREENHOUSE Study Year: 1986 Year started: 12/17/1986 Year ended: //1987. Three week old plants were placed in a petri dish containing ten milliliters of a 108 suspension of C. sepedonicum (control plantings were put in buffer). The roots were then injured by cutting the root tips. After one hour, the plants were transplanted. Visual evaluations were made at four and eight weeks and each accession was assessed a rating (0-3).

The screening took place in the greenhouse located at the Washington State University / USDA-ARS Research Station Campus by Prosser, WA. The study was carried out in pots. Initially, true potato seeds (not tubers) of 40 accessions of S. tuberosum subsp. andigenum were grown and 15 plants were selected to represent each accession. The first screening trial was carried out during 2007, with Russet Burbank and Ranger Russet as industry standards for comparisons. Among the 40 accessions screened, 5 demonstrated less (P<0.05) disease on both root and stem compared to the standard cultivars. These 5 accessions were considered "potentially resistant" to black dot. In 2009, a fresh batch of 100 seeds of each of the "potentially resistant" accessions was obtained. The seeds were grown into plants, each a unique genotype, and from each accession 10-15 genotypes were selected based upon their vigor. The genotypes were propagated into multiple copies (clones) and were maintained as plants in the greenhouse, as tissue cultures and as tubers. The genotypes were screened with 8 to 26 replications each; and resistance was recorded based upon stem colonization in comparison to Russet Burbank, Shepody and Umatilla Russet that were used as industry standards. Five black dot resistant clones were identified from the accession PI243367 and 2 from the accession PI230470.

METHOD: Visual Examination CONDITIONS: Green House - 18h light at 18-24C. METHOD NARR: Freshly cut leaf petioles were inserted to about 5mm in 50 grams of sterile sand drenched with 17ml of inoculum. The length of the rot develocorded 72 hours post-inoculation. Hybrid and cultivar scores are also reported. Wild species were tested using 5 petioles and the experiment was repeated once. RESULTS NARR: A large # (50 0f 162) of chc, and a high % off 6, 50%) were resistant or highly resistant. 100, 97 and 95% can, tarand spg clones were eiter susceptible or highly susceptible, respectively. AUTHOR EXPLANATION: Mean rot lengths: 0-5mm = Highly Resistant, 6-10mm = Resist >50mm = highly susceptible.

ISO 121 - Visual Examination. CONDITIONS: Growth Chamber and Green House - 12h light with 90% R.H. at either 18 or 24C in GC. 20C GH METHOD NARR: Two inoculation methods were used. Stem immersion method: Stems were taken from tubers and immersed in bacterial suspension for 30 minutes. Stems were then planted and transferred to a growth chamber. After 12 days symptoms were assessed. Stem injection method: Seven week old plants were inoculated with 5ul of bacterial suspension using a hypodermic syringe. They were then placed in a (20C) temperature controlled GH. Symptoms were recorded 15 days post-inoculation. RESULTS NARR: Correlation coefficients between the two methods were highly significant when innoculations were made both with Eca and with Ecc. Stem immersion method: Resistant = <15% of stems with symptoms, Intermediate = 16-25% of stems with symptoms, Susceptible = >26% of stems with symptoms. Stem Injection Method: 1 = no symptoms, 2-3 = brown and dry necrosis < 1cm at the inoculation site, compartmentized cancer, 4 = brown rot 2-3cm from the inoculation site, active cancer, 5= brown necrosis > 3cm. Resistant=2-4mm, Intermediate=4-6mm and >6= Susceptible diameter rots. AUTHOR EXPLANATION: Findings indicate that resistance to blackleg in the 2 species of Erwinia is controlled by the same mechanism or, that genes with pleiotropic effect control the resistance to Eca and Ecc.

METHOD: Visual Examination CONDITIONS: Green House METHOD NARR: A number of variables were tested to find the most effective method of inoculation. The most effective involved crushing the leaf and petiole with a forceps and thek old seedlings with bacterial suspension. Seedlings were maintained in a mist chamber at 20C before and after inoculation. In the first screening, utilizing three subspecies of Erwinia, disease severity was recorded as per In the second screening, only Ecc was used to inoculated and disease severity was ranked 0-4. The disease index for different accessions was calculated as a mean value for all inoculated seedlings. Seedlings were also inoculstant strain of Ecc SR 394 to determine external and internal survival of the bacteria by dilution plating. RESULTS NARR: In resistant lines, disease severity was often very low even when extremely high levels of bacteria are used. in a given symptomless vs diseased plant were apparently not directly correlated with disease severity. AUTHOR EXPLANATION: These seedling results may not accurately reflect resistance in older plants.

METHOD: Chemical Assay CONDITIONS: Field METHOD NARR: Tubers that had been stored for 3 months were surface sterilized. Pipet tips containing a suspension of the bacteria were pressed to a depth of 10mm and left in place. Aftern, the tubers were sliced vertically through the infection points and the width of decayed tissue measured. Seperate innoculated tubers were sliced vertically to the injection points and tissue surrounding the injection sit to determine the activities of PPO and PO. RESULTS NARR: Parental, fusion hybrid and cultivar material was used. Hexaploid somatic hybrids of brd and tbr cv Russet Burbank showed PPO activity 2 times higher than Russet Burb of the hybrids was also higher in the periderm and medullary tissue. Results also show resistance to bacterial soft rot in the hybrid tubers. Wounding and infection induced an increase in PPO and PO activities in all samples tested,s higher and better stabilized in the hybrids. AUTHOR EXPLANATION: The results showed that the high activity of phenol oxidating enzymes may be one of the factors that affect the periderm resistance to bacterial soft roe overall resistance mechanism. Anaerobic conditions exclude the functioning of PPO and PO.

ISO 009 - Visual Examination. CONDITIONS: Growth Chamber and Green House - 12h light with 90% R.H. at either 18 or 24C in GC. 20C GH METHOD NARR: Two inoculation methods were used. Stem immersion method: Stems were taken from tubers and immersed in bacterial suspension for 30 minutes. Stems were then planted and transferred to a growth chamber. After 12 days symptoms were assessed. Stem injection method: Seven week old plants were inoculated with 5ul of bacterial suspension using a hypodermic syringe. They were then placed in a (20C) temperature controlled GH. Symptoms were recorded 15 days post-inoculation. RESULTS NARR: Correlation coefficients between the two methods were highly significant when innoculations were made both with Eca and with Ecc. Stem immersion method: Resistant = <15% of stems with symptoms, Intermediate = 16-25% of stems with symptoms, Susceptible = >26% of stems with symptoms. Stem Injection Method: 1 = no symptoms, 2-3 = brown and dry necrosis < 1cm at the inoculation site, compartmentized cancer, 4 = brown rot 2-3cm from the inoculation site, active cancer, 5= brown necrosis > 3cm. Resistant=2-4mm, Intermediate=4-6mm and >6= Susceptible diameter rots. AUTHOR EXPLANATION: Findings indicate that resistance to blackleg in the 2 species of Erwinia is controlled by the same mechanism or, that genes with pleiotropic effect control the resistance to Eca and Ecc.

METHOD: Chemical Assay CONDITIONS: Green House METHOD NARR: Upon maturity, the tubers of chosen accessions were harvested and processed for melanin formation and PPO activity. Crosses of hjt clones showing low melanin formationcultivated diploid potatoes were conducted. Degree of dominance was measured and PPO rate was calculated. RESULTS NARR: Melanin formation showed a pattern different from PPO activity. Between-accession variation was signor melanin. There is considerable within-accession variation, producing mean differences that are significantly different within accessions for both traits. Genetic control of factors responsible for very low PPO and lack of eented together in hybrids is dominant to the higher melanin formation and higher PPO activity in the cultivated parent. AUTHOR EXPLANATION: A large reduction of PPO activity in the tubers may reduce melanin production.

METHOD: Chemical Assay CONDITIONS: Green House - 21C METHOD NARR: Enzyme assays, Northern and Western Blotting, were performed to determine PPO protein and mRNA levels in hjt tubers. The goal of the analysis was to compare relatbr and hjr. RESULTS NARR: Enzymatic activity was not detected in any preparation of hjt, neither crude nor purified. AUTHOR EXPLANATION: Hjt does not exhibit enzymatic browning or blackspot because it does not have enzya suggests that tubers of hjt produce PPO mRNA and protein, but that the protein may be structurally altered or lacking a cofactor and therefore inactive.

METHOD: Chemical Assay CONDITIONS: Green House - 14h declining to 9h METHOD NARR: Plants were watered with either of 2 nutrient solutions. The control watering solution was 1/4 strength Hoagland's solution. The treatment solutiing the control solution to 800 ppm calcium with calcium chloride. Tuber tissue was processed and assayed for overall ppm calcium on a dry weight basis on whole tubers by atomic absorption spectrophotometry. The mean tuberl unit was calculated. RESULTS NARR: Where (T) = treatment and (C) = control the (T-C) statistic represents the efficiency of accumulation of supplemental calcium. The (C) statistic represents the ability of tubers to accumumented calcium environment. AUTHOR EXPLANATION: The observed decrease in calcium ppm associated with larger tubers is not associated with the decreased proportion of peel tissue in larger tubers, but suggests that some of the specieger tubers are also poor calcium accumulators.

METHOD: Chemical Assay CONDITIONS: Green House and Field METHOD NARR: Plants were watered with either of 2 nutrient solutions. The control watering solution was 1/4 strength Hoagland's solution. The treatment solution was maderol solution to 800 ppm calcium with calcium nitrate. Tuber tissue was processed and assayed for overall ppm calcium on a dry weight basis on whole tubers by atomic absorption spectrophotometry. Outstanding populations were93 random seedlings were chosen from populations of the three outstanding selections. In 1994 these selections were grown in the field and tuber tissue was analzed. In 1995 progeny were obtained by crossing selected genotypesthen compared to a random sample of individuals from the original populations. RESULTS NARR: Since tuber peel contains much more calcium than the flesh, observed calcium levels of entire tubers should be adjusted so that species proll tubers can be more accurately compared. If this is done, ktz selections are no longer significantly higher than cultivars, but mcd selections still are. The 1995 tests show that populations can be changed by recurrent Continued fine screening and recurrent selection may be able to produce populations uniformly extreme (homozygous) for as many as possible of the gnes that contribute to extreme tuber calcium.

86 populations of microdontum were tested as tubers made in the winter of 2006-2007. 12 plants were tuberized for each pop and watered with 500 ppm calcium solution. After harvest, tubers were then sliced, dried, ground, ashed, and analyzed for calcium content (ppm of dry weight) by atomic spectrophotometry absorption. (Testing year average = 1521 max = 2830 min = 776)

86 populations of microdontum were tested as tubers made in the winter of 2007-2008. 12 plants were tuberized for each pop and watered with 500 ppm calcium solution. After harvest, tubers were then sliced, dried, ground, ashed, and analyzed for calcium content (ppm of dry weight) by atomic spectrophotometry absorption. The average ranks were ranked, resulting in 53 unique average rank levels (several populations had equal average ranks, so only 53 rank levels, not 86). (Testing year average = 1113 max = 2053 min = 477)

Study Name: Resistance to Meloidogyne Chitwoodi Nematodes Experiment Type: Screenhouse SCREENHOUSE Study Year: 1985 Year started: 12/10/1985 Year ended: 04/01/1986. Eight week old seedlings were inoculated with 3000 second stage larvae. Three months later, roots were examined for galls and each accession was given a gall rating (0-5).

Study Name: Resistance to Meloidogyne Chitwoodi Nematodes Experiment Type: Screenhouse SCREENHOUSE Study Year: 1985 Year started: //1985 Year ended: 12/28/1986. Cuttings were taken from ten seedlings and allowed two weeks for root growth. They were then inoculated with 2000-3000 eggs by dispersing them over the soil. After a 60 day inoculation period, the plants were examined for root galls and given a gall index (0-5). The roots were then examined for egg masses and given an index rating (0-5). A reproduction rating (.01-80.90) was also calculated for each accession.

Both ELISA and Visual Examination METHOD NARR: Wild Solanum species were mechanically inoculated with diluted sap of Nicotiana previously infected with the HeMV-W/H isolate. Visual inspection and ELISA were used to check susceptibility. Symptomless plants were back-inoculated on indicator plants. No specific ELISA values were given. AUTHOR EXPLANATION: This data draws attention to the potential source of danger represented by HeMV susceptible wild solanum species for both breeders and for finding resistant accessions.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 16h light with daily mininum temp 19C and maximum 26C. METHOD NARR: CMV-infected tobacco plants were used for side-graft inoculation of 4 plants of each genotypeved up to 6 weeks and virus titres were measured by ELISA at 4 and 6 weeks after inoculation. RESULTS NARR: Fny-CMV did not cause symptoms, A9-CMV caused mosaic, and LS-CMV caused stunting and narrow, wavy leaflets, and thrated increasing virus titres in palnts. AUTHOR EXPLANATION: Mosaic symptoms were attenuated to some extent with sunny weather and rising maximum temperatures. Systemic necrosis continued to develop during the warmer growin

Plantlets are grown in jiffy-mix in 3" pots until the first vigorous roots reach the inside edge of the pot. Root tip samples of about 1/2" are then collected in the early morning and soaked in a .29% solution of colchicine for about 5 hours. After the samples are put into fixative for 24 hours, they are ready for analysis. To prepare for analysis, cook the samples in 1N HCl at 60C for about 12 minutes and then transfer the sample into water. The samples can then be macerated, stained, and prepared on a slide for microscopic observation.

DNA was extracted from bulks of 27 plants from each of 94 populations to generate AFLPs. A total of 1,741 informative loci were detected. AFLP loci were treated as though they were traits, with the banded condition considered to be the desired state to include in a core set. At least one band unique to a population was present in 45 populations, and these 45 populations together captured 98% of all bands. Adding another 14 populations for a core of 59 populations captured 100% of bands. This core set was assessed for whether it encompassed those populations known to have useful traits, including nutritional and quality components; and disease, stress and pest resistances. As with AFLP bands, 25 out of 26 of the most desirable phenotypic traits were also found in populations in the core set of 59 populations. The most desirable status of 3 traits is lost by selecting a core of 45 populations. We conclude that these core sets would be a rational starting point when prospecting for new useful traits in microdontum. Populations in the core of 59 are ranked by number of bands contributed. A researcher planning an experiment which needed to limit the number of populations evaluated could compose a sub-core of required size by progressively selecting populations with higher band capture ranks, thus maximizing total bands captured. Lower numbered Band capture Rank populations captured more unique AFLP bands.

Study Name: Accessions select to core collection. Methods: Accessions were selected into the core if there were less than 100 accessions per species or by location and taxonomy for species with more than 100 accessions.

METHOD: Test Diet CONDITIONS: Field METHOD NARR: Accessions were planted in the field and examined for defoliation with counts of larvae and adults present monitored over a three season period. RESULTS NARR: Fine screening revssions previously identified as uniformly and highly resistant some genotypes deviated significantly from the accession mean for one or more resistance parameters. The heterozygosity indicates a less than optimal breeding vault counts were not useful in gauging differences in CBP resistance among accessions or genotypes. Number of larvae best differentiates among genotypes because larval counts combine the effects of oviposition and survival.

METHOD: Test Diet CONDITIONS: Green House METHOD NARR: Adults and larvae were given leaf disks to feed on. Preference of adults was measured by assessing left over disc weight (rather than area). Larval weight gain and leaf conusing 4th instar larvae. Larval development rate was assessed using neonate larvae. RESULTS NARR: In choice tests with adults and larvae both, Kennebec was prefered. In no choice tests, the differences between the PI acce. AUTHOR EXPLANATION: Three tests were used: Foliage consumption in adults, weight gain in 4th instar larvae, and larval development and mortality. All three tests gave significant differences with sufficient replication.sured neonate larvae development after 3-4 days of feeding.

Study Name: Resistance to Colorado Potato Beetle. Experiment Type: Field FIELD Study Year: 1985 Year started: 04/30/1985 Year ended: 01/30/1986. Seedlings were germinated in the greenhouse and then transplanted to the field. Visual observations were made three times during the growing season and the defoliation percentage (0-100) was noted.

METHOD: Test Diet CONDITIONS: Green House - 16hr light at 20-26C with 60-90% RH METHOD NARR: Foliar glycoalkaloid content was determined. Foliar PPO content was measured. Neonate larvae were confined on plants and mortality ande determined at 2-day intervals. Resulting adults were assessed for fecundity. RESULTS NARR: No glycoalkaloids were detected in foliage of ber 437334. No significant differences were observed in fecal content. A highlyon was observed between larval weight and PPO. A significant positive correlation was found between PPO levels in the potato leaves and CPB larval mortality. A significant negative correlation was found between number of eggs. Total PPO in foliage was sttrongly negatively correlated with relative growth rate of larvae. AUTHOR EXPLANATION: This study suggests that PPO has a negative effect on CPB. Results also suggest that solasonine and solmargine dohe resistance shown here.

METHOD: Feeding Behavior CONDITIONS: Field METHOD NARR: The total glycoalkyloid concentration in foliage was determined using ELISA. The weight and developmental stage of the larvae on different host plants were determined dailyThe susceptibility to fungus of insects reared on different host plants was determined in a bioassay. Insects were dipped in fungus and returned to host plants. Mortality was assessed daily for 8 days. RESULTS NARR: Therean weights of larvae reared on the different plants. Pupae reared from ktz 472925 and chc 189220 weighed significantly less than those fed tbr (Lenape). Tere wre no significant differences in the duration of a particular insth host. The survival of larvae through each instar on the different hosts varied significantly. Rearing larvae on different hosts did not cause significant differences in their susceptibility to B. bassiana.

METHOD: Life Cycle CONDITIONS: Green House - 16h light at 20-26C with 60-90% RH METHOD NARR: Neonate larvae were caged on plants. Some of the ncd had exudate of trichomes removed by wiping. Living and dead larvae were recorded. and relative consumption rate were calculated. Oviposition behavior was also examined. In field trials 2 ber accessions were added to the ncd and tbr groups for defoliation assessment. RESULTS NARR: Larvae confined to night, and experienced significantly higher mortality than on tbr. Removing exudate did not improve survival. On ncd, most larvae died as first instars and those that survived, did not complete the second stadium in the time alncd contained few eggs and those females fed on ncd virtually ceased oviposition. Defoliation of ncd was very low and were < or = to ber. AUTHOR EXPLANATION: Resistance appears to be largely independent of glandular trichomes. Feeterred and it is difficult to determine the relative importance of behavioral inhibition versus metabolic toxicity since few larvae fed sufficiently to allow accurate determination of growth efficiency. Preliminary analymatine.

METHOD: Feeding Behavior CONDITIONS: Field and Lab - 16h light at 20-26C and 60-90% RH METHOD NARR: The effect of larval body size on acquisition of trichome exudate was examined. This was done both in the lab using detatched lld. The effect of environment on trichome density was also examined. RESULTS NARR: The # of tarsi bearing exudate increased significantly as successive larval instars were confined for 24h on ber 310927. This accession atarsal encasement than the others tested. Both 1st & 3rd instars collected far less exudate in field plots of ber than in lab tests. The environment did not significantly influence type A trichome density, while for type B itaxial surface. AUTHOR EXPLANATION: The tendency of young CPB larvae to feed on the underside of leaves may explain the lower incidence of exudate accumulation on sone accessions. Large larvae acquire exudate more rapidly than do sm indument of trichomes may simply deter or physically prevent larvae from setting into a suitable feeding site, and spending more time on grooming or searching activities.

METHOD: Feeding Behavior CONDITIONS: Green House - 16h light at 20-26C with 60-90% RH METHOD NARR: Larvae of different stadia were confined without choice in containers with excised foliage. The # of larvae in contact with the fand the # resting were recorded after 30 min. and at hourly intervals for 6 hours. The observations were repeated using leaves that had been gently rubbed to remove trichome exudate. RESULTS NARR: Larvae were less frequen0927. Removal of the exudate had little effect on the tendency of first instars to move away from ber, but led to a higher frequency of feeding than observed on leaflets with intact trichomes. Only first instars ehibited true those that remained on ber, and this effect disappeared when exudate was removed from leaflets. AUTHOR EXPLANATION: Older larvae move off of ber leaves quickly while it takes smaller larvae considerably longer.

METHOD: Visual Examination ; Body Count CONDITIONS: Field METHOD NARR: CPB evaluations were scored by noting the percent defoliation of plants in the field. The accessions were grouped according to mean evaluation and these grouer numbers 1-6. PLH and PFB scores were generated by vacuuming plot samples. The plants were also rated on size so that an adjustment could be made for this parameter. The insects present were counted and the adjustmentshe accessions into clusters 1-4 (PLH) and 1-5 (PFB).

METHOD: Light Levels CONDITIONS: Green House - 16h light METHOD NARR: Plant measurements: leaf and leaflet area, trichome-specific phenolic oxidation activity (MEBA), trichome density and gland volume were measured for two lightpal development were monitored on the plants used in the light level study. Finally, reproductive performance was also measured. RESULTS NARR: Light level did not affect leaf or leaflet area. Browning activity of ber foliding produced a 36% decrease in gland volume of type A on 473331 while 473334 was unaffected. Shading produced a 35% reduction in densities of type B on 473331 and 44% reduction in volume of type B exudate. Light level did notl or adult weight, larval survival or development time. Larval survival on tbr was twice that on ber473331.Females on ber were lighter than initial weights. Preadult development time on ber was delayed 3-4 days. Light level did not reproductive performance. AUTHOR EXPLANATION: Ber resistance was stable despite shading, which dramaically altered plant growth habit and significantly reduced trichome density, gland volume, and trichome phenolic oxi

METHOD: Fecundity METHOD NARR: Cohorts from the base CPB population were reared for 10 consecutive generations on each of three hosts (tbr, ber 473331 & 473334). Fecundity is measured. Size and appearance of fat body, ovaries an examined. RESULTS NARR: Ovaries of females reared on ber were less well developed than on tbr. In contrast, fat bodies were more developed on females reared on ber. The midgut of tbr fed females was white or pink in colwere brown or gray, enlarged and contained large amounts of undigested plant material. Ber fed females also showed dark hardened pellets in posterior midgut which seemed to be undigested trichomes. AUTHOR EXPLANATION: This wation of the Ph.D dissertation of F.H. Franca and much of the growth and background information is found there. Author suggests different interpretations of data. Lack of ability to use ber may decrease size of ovaries and increase fInefficient foliage use may also lead to overload of the digestive system. Reduced fecundity on ber is probably due in part to physiological and morphological abnormalities.

METHOD: Life Cycle CONDITIONS: Green House - 16h light at 22-27C and 40-60% RH METHOD NARR: Larvae were confined on leaves and allowed to feed. Fourth instars were monitored closely and removed from the cages to pupate. Develop were calculated and weight was measured. Groups of adults were isolated on plants and cages were monitored daily, egg masses removed and # of eggs per mass determined. RESULTS NARR: Mortality of adults, larvae and pupae on tbr. Duration of pupation on ber was greater than on tbr. Tbr reared females produced more eggs than those on ber. Averaged over all generations, net replacement rates on ber were 80% less than on tbr. AUTHOR EXPLANATIONdaptation of CPB to resistant potato genotypes is unlikely to occur as rapidly as previously reported.

METHOD: Life Cycle CONDITIONS: Field METHOD NARR: Newly emerged adults were released on field plots (both caged and uncaged) of tbr and ber. These adults were marked with paint. All life stages were monitored and counted to detine and number of eggs laid per mass. Overwintering on the two species was also assessed. Fecundity was measured using four different treatments. RESULTS NARR: All 4 instars developed more slowly on ber than on tbr. Beet plots resulting in population declines. Oviposition in field cages was much greater on tbr than ber. First generation larval survival was lower in ber plots than tbr plots. Larval survival on tbr decreased with increased egoccurred during the first instar on both hosts. On ber, oviposition increased in the 2nd generation. The winter survival was significantly lower on ber than on tbr. First generation of females raised on ber had lower oviposition. Tce in survival between larvae completing their third generation on ber than those on tbr. AUTHOR EXPLANATION: Authors indicate that CPB adapts to resistance of ber rather quickly (two generations).

In 2006, 12 random seedlings per accession were transplanted into each of two replications at the Hancock Wisconsin Agricultural Experiment Station. A randomized complete block design was used. Four tubers from Red Norland potatoes also were planted after every 10 plots to provide susceptible check plants. Standard irrigation and cultural practices were used in the field, except that pesticides were not used to control Colorado potato beetle. Each plot of 12 plants was visually scored for percentage of defoliation on 2, 9, 16, and 22 August (Horton et al. 1997). The area under the defoliation progress (AUDPC) curve was calculated for each accession based on percent defoliation on the four score dates. Low scores indicate resistance to CPB.

In 2007, 12 random seedlings per accession were transplanted into each of two replications at Hancock in a randomized complete block design. As in 2006, Red Norland was included as a susceptible check. Standard cultural practices were used in the field, except that pesticides were not used to control Colorado potato beetle. Individual plants in each plot were scored for percent defoliation on 2, 9, and 16 July and 1, 13 and 21 August. The AUDPC was calculated for each accession based on mean larval defoliation scores on the six score dates. Low scores indicate resistance to CPB.

Resistance to Colorado beetle was made simultaneously in the field in natural conditions where the number of larvas were counted on untreated (by chemicals) plants of potato during the 2-3 generations. Computed data is the average of number of larva on 1 plant.

METHOD: Test Diet CONDITIONS: Green House - 16h light at 20-26C and 60-90% RH METHOD NARR: Ber leaflets were dipped in methanol to remove type B exudate. Wiping with a cotton swab removed most of the type A trichomes as well asdate. These leaflets were placed in petri dishes and larvae were allowed to feed. Sucrose esters were prepared from a difference accession of ber. These esters were coated on methanol-dipped ber discs or untreated tbr disc neonate L1's failed to feed when given ber leaflets for 72 hr. Mortality was restricted to those that did not feed or fed very little indicating starvation. Removal of ber trichomes improved both feeding and survival. Methanwith sucrose esters lowered feeding to levels of untreated disks. This effect was reversed with removal of type A trichomes indicating they work in concert. Type B exudate inhibits feeding only in the presence of type A trichomes. Tof allelochemical in ber foliage that adversely affect feeding. AUTHOR EXPLANATION: The sucrose esters are not normally distributed uniformly on foliage, but are concentrated in droplets on the tips of type B stalks. Ee A trichomes had been removed, L1's grew less rapidly than on tbr. This could be due to either a lower nutritional quality of ber foliage, or reduced consumption rate or a combination of the two.

METHOD: Feeding Behavior CONDITIONS: Green House and Field - 16h light at 20-26C and 60-90% RH METHOD NARR: Plants grown from seed were transfered to the field and assessed for field resistance. Selected plants were removed fromin the GH. PI 473331 had two siblings, one resistant and one susceptible, selected. Larvae were placed on excised leaflets and activities (walking, feeding, resting) were monitored for 5 minutes. In 24 and 72 hr leaf testsand inspected for evidence of feeding (24 hr) and survival (72 hr). F6 tbr x ber hybrids were also assessed. RESULTS NARR: Larvae that fed took as long to initiate feeding on tbr as on ber. The duration of feeding and % tion ber. Time spent resting was similar on all hosts. Feeding on ber was less than on tbr. In caged larvae, feeding was lowest on ber. Larvae developed significantly slower on ber. Larvae on the most resistant plants had the highesncasement by trichome exudate. AUTHOR EXPLANATION: Much of the resistance of ber is expressed by failure of newly hatched larvae to initiate feeding leading to starvation and death. High trichome density may deprive laface eliminating the appropriate cues for initiation of feeding. The relative resistance of the accessions follows: 310927>265858>473334>473331>tbr x ber hybrid>tbr cv. Katahdin

METHOD: Test Diet CONDITIONS: Lab METHOD NARR: Ber 473340 has two clones named 1726 and 1729 which differ in the type of trichome found on leaves. Types A & B on 1726 while 1729 bears only type A. A no-choice bio-assay was condas well as tbr leaves treated with ber extracts. Consumption was measured by area. Overwintered and first generation adults were also tested. RESULTS NARR: The overwintered beetles consumed ~ half the amt of foliage of fConsumption of tbr treated with ber1726 extract decreased linearly as the extract concentration was increased. The presence of type B exudate on tbr reduced cunsumption of first generation beetles. AUTHOR EXPLANATION: The drp of a long hair, constitute a barrier of concentrated feeding deterent and may be more effective than the extract spread on the surface of the leaf. Results support the conclusion that the trichome B exudate is the active fraction ofract and that the resistance of clone 1729 is based on a different mechanism.

METHOD: Life Cycle CONDITIONS: Lab - 16h light at 21-28C METHOD NARR: CPB's were raised and egg masses were collected. Eggs from each parent were divided and placed on tbr and ber. Larvae were grown and assessed for development emerged as adults they were fed with the same species. Fecundity was measured as total number of eggs produced during first 15 days of adult life. Developmental time and survival for each instar and the pupal stage were restical differences were found in the developmental time of all stages of beetles grown on ber compared with tbr. Survival rates were lower on ber than tbr except for the pupal stage. Fecundity was higher and preoviposition timr. A variety of analyses were performed to determine variance according to sex, sire, dam, host and combinations thereof. AUTHOR EXPLANATION: Results indicate that a portion of the CPB population could utilize ber. However, the dimeters were not equally effected by the plant species. Survival and fecundity were reduced and more variable on ber than tbr, but development time, prepupal weight, and egg weight varied less between plant species.

METHOD: Mortality CONDITIONS: Field METHOD NARR: Adult and larval fitness were tested in field cage experiments. All cages were sampled multiple times per week to record mortality, sex, missing beetles, # of egg clutches and # oboratory tests using neonates were also conducted to track mortality and instar. RESULTS NARR: In Adult field cage experiments: mortality was 25% or less on tbr, ber and cap and varied from 30-70% on the other species. Nootal # of eggs laid was <15% of tbr for cap, jam, pnt, pld, trf with tar at 69% and ber at 43%. In Larval field cage experiments: 1st instar mortality was high in pld, pnt; moderate in jam, trf; low in ber, cap and tar. In theall larval mortality was higher on pld, pnt, trf and jam. Develpoment took longer on cap. Pnt was unique in that larval mortality was high but adult mortality relatively low. AUTHOR EXPLANATION: In the experiments presented, the rity of adults and larvae, the reduced oviposition, the low proportion of adults recovered 2d after release and the develpoment time similar to tbr indicate the presence of semiochemicals in ber. Factors providing resistancrom those in ber. Tar & ber may have a similar mode of resistance. In jam, pld and trf there may be substances interacting with insect physiology or as a feeding deterrent reducing or inhibiting food ingestion.

METHOD: Feeding Behavior CONDITIONS: Field METHOD NARR: Plants were grown in the field where data was collected on # of adults, egg clutches, instar and % defoliation. Laboratory tests were also done to observe feeding behaviording and contact) on the different accessions. Choice tests, larval development, adult foliage consumption, survival and oviposition were also conducted in the laboratory. RESULTS NARR: Population density of all developme on wild species than tbr. The average number of adults tnded to be higher on tar than opl or oka. Adults and larvae spent more time feeding on tbr than wild species and oka had the lowest feeding frequency. Resting and walkis was greater on wild species. Adults walked more but resting was similar on wild vs tbr. Conact was reduced on wild accessions. Larval development varied among the species used. Wild foliage was consumed much less than tbr. AUTHO affected adults and larvae differently. This effect is based primarily on an antifeedant or deterrent effect that mainly affects the adults and reduces egg laying. It is unlikely that glycoalkaloids play an important roes studied and their presence does not explain the different modes of resistance exhibited.

METHOD: Life Cycle CONDITIONS: Field METHOD NARR: For each plant, the # of adults, egg clutches, instars, and % defoliation were recorded. RESULTS NARR: CPB was less abundant on all wild species accessions than on tbr. More wd tar than on other wild species. Defoliation was low on all wild species. AUTHOR EXPLANATION: These results confirm the fact that antixenosis plays an important role in the resistance of these Solanum species. Ber demonntibiosis. Few beetles were found on cap, jam, pnt, trf. Antibiosis was the most important mode of resistance in pld.

Study Name: Resistance to Colorado Potato Beetle. Experiment Type: Field FIELD Study Year: 1984 Year started: 04/01/1983 Year ended: 08/05/1984. Twice during the growing season a defoliation rating (0-3) was given to the plots by visual observations.

METHOD: Test Diet CONDITIONS: Green House - 14h light at 18-29C METHOD NARR: Leaflets from one side of a leaf were sampled and pooled for SGA analysis. Larvae were allowed to feed on leaf disks cut from leaves opposite those sam consumed was measured. Hybrids of phu and chc were also evaluated. The predominant SGAs, solanine and chaconine, leptine and leptinine, were extracted and hydrolyzed to their corresponding aglycons, solanidine, leptinidinentified using capillary gas chromatography. RESULTS NARR: Chc contained solanidine (confirming presence of solanine/chaconine) leptinidine and acetylleptinidine (indicating presence of leptinidines and leptines respectively).ly lower feeding rates on chc in both experiments. AUTHOR EXPLANATION: Concentrations of ALD, the aglycon of leptines, were significantly correlated to feeding supression by CPB, indicating leptines were more important than other SGtent in predicting feeding rates.

Study Name: Resistance to Colorado Potato Beetle. Experiment Type: Field FIELD Study Year: 1984 Year started: 04/13/1984 Year ended: 11/01/1984. Four replications of three four week old seedlings were transplanted to the field. Damage evaluations were made six times in July, and the plots were each given a rating (0-5).

Study Name: Resistance to Colorado Potato Beetle. Experiment Type: Field FIELD Study Year: 1984 Year started: 04/29/1983 Year ended: 12/15/1983 Comment: Twelve clones of each accession were randomly planted in a quarter acre block. Each accession was put into a rating class (0-5). A mean of the four replications was found and percentiles were based upon these mean values.

METHOD: Life Cycle CONDITIONS: Green House - 16h light at 23-25C METHOD NARR: No-choice experiments were used to determine leaf consumption and the effect of feeding on larval development. Mortality rates were monitored. Trichooalkaloid analyses were done. Quantitation and characterization of total foliar gycoalkaloids were accomplished using thin-layer chromatography. RESULTS NARR: Considerable inhibition of leaf consumption by larvae was show310926, ber265858, and chc320123. All accessions showed a significant decrease in larval mass except rap. The highest larval mortality rates were on trf283104, chc320123, ber265858 and ber310926. Ber had the highest density o Trf had ~one-third the density of ber whith both types lacking glands. Crc had no visible trichome structures. TGC were low in crc and trf; medium to low in rap and chc320311; high in ber and chc320123. The most abunfdant glycoalka and soanine. AUTHOR EXPLANATION: Trf, which has no glandular trichomes, or detected glycoalkaloids, demonstrated antifeeding and developmental retardant levels comparible to ber. Trf accessions exhibited effective ressed by an antinutritive or deterrent mechanism.

METHOD: Test Diet CONDITIONS: Green House and Lab METHOD NARR: In a study by Sinden et al 1986, high and low leptine clones of chacoense accessions were identified. The current work is a continuation and uses some of these clonlyses were performed. Adult CPBs were used in infest field plots. The # of adults and degree of feeding damage to the plants was measured. Adult feeding rates were measured using leaf disks, and larval development was meaESULTS NARR: Chc217451 with high levels of commersonine and demissine had the fewest adults and least feeding damage. The most susceptible clone was 320287 and the most resistant was 458313. Leaf Disk Test: feeding was deterrelated with leptine content. Larval Development: Differences in weights, development and survival on high vs low leptine clones were significant. AUTHOR EXPLANATION: High and low leptine sibs were compared. Those with high levelmore resistant than the average clone. The low to mid range sibs better represented the average chacoense clone in leptine level and resistance. The highest leptine level clones are highly resistant to larvae and nearly

Study Name: Resistance to Colorado Potato Beetle. Experiment Type: Field FIELD Study Year: 1984 Year started: 04/03/1984 Year ended: 08/30/1984. Two different plantings were made in this evaluation. Four replications of three seedlings were planted, one was used as a control plot. Plants were given consumtion ratings (1-4) made in August.

METHOD: Test Diet CONDITIONS: Green House METHOD NARR: Two bioassays were performed using tbr cv. Atlantic. The first with tuber disks treated with ber473334 extracts. The second with leaf disks treated with the berthaultii extere divided into volatile and non-volatile as well as internal and external fractions. CPB were allowed to feed. RESULTS NARR: Increasing concentrations of ber leaf rinses applied to tuber disks resulted in linear decreaslarly, feeding decreased in the leaf disk assay, but in an exponential fashion. The nonvolatile fraction was deterrent, while the voltile fraction tended to reduce consumption, but not significantly. Neither fraction was as de AUTHOR EXPLANATION: Authors hypothesize that the feeding deterrents are produced by the type A trichomes.

METHOD: Feeding Behavior CONDITIONS: Green House - 16h light at 27C and 50% RH METHOD NARR: Excised leaflets were arranged in a preference arena, and CPB were allowed to orient freely for the choice preference test. Leaflets ofssed to both surfaces of tuberosum leaflets to determine if resistance was localized in trichomes. Trichomes were also removed to see what effect that would have on choice. The trichome removal experiments were repeated us preference data were recorded after 24 hrs. RESULTS NARR: Adults and larvae preferred tbr in choice tests. Given a choice of the two ber accessions, feeding was reduced and no preference was detected in adults. Choice betwresulted in a decrease in the initiation of feeding and no preference. When ber leaflets were appressed to tbr leaflets, the non-appressed control tbr were preferred. Choice between trichome 'intact' or 'removed' resulted in preferen trichomes removed, and the preference increased as degree of removal was increased. Complete removal of trichome resulted in feeding levels close to tbr. AUTHOR EXPLANATION: The increase in adult feeding with trichomedegree of trichome removal. This work supports the hyothesis that type A trichomes are required for expression of resistance, while type B sugar esters may enhance the effect. The expression of resistance is dependePB.

We discovered a mutant in wild potato species that produces abnormal flowers. Instead of the usual bud leaves (sepals), petals, male and female organs, these mutant "flowers" have only repeating whorls of sepals, thus the name, "crazy sepal." This could be a useful tool for studying flower development and other practical features of reproduction and physiology.

Virus free in vitro clonal cultivar stocks were obtained from the US Potato Genebank collection and three plants each were transplanted in two replicated field plots at Sturgeon Bay, Wisconsin in 2009. Representative tubers were washed, peeled, chopped and weighed for a sample of about 250 gm fresh weight, then air dried at about 50C to stasis and weighed again for calculation of the dry matter percent statistic.

We grew 15 seedlings of each population in 6" clay pots in the winter greenhouse 2007-8, 2008-9 and 2009-10 for tuberization. Tubers were harvested when mature, and bulked by population. They were not peeled. They were washed, weighed, and frozen, then freeze-dried and weighed again. Percent dry matter for each population is average of dry wt / wet weight over the three years.

Three whole field tubers (if medium or small) or longitudinal sections (if large) were peeled (except as noted) for about 250 g of tissue for each sample. They were rinsed with tap water and rinsed with distilled water. Water was allowed to drip off, and tubers were sliced into french-fry style pieces with a Vadalia Onion Slicer. The pieces were put in a blender cup, nylon slipper sock stretched over, and contents shaken into the sock. Sample bags were put on black flats over plasticized paper and placed back in 40F cooler. When all samples were prepared, they were taken out again for weighing. They were then put into a warm air dryer at 130F until weight was stable. Dry/fresh weights was the calculutation for % dry matter. Figures usually represent two replications from separate field plots.

Three whole field tubers (if medium or small) or longitudinal sections (if large) were peeled (except as noted) for about 250 g of tissue for each sample. They were rinsed with tap water and rinsed with distilled water. Water was allowed to drip off, and tubers were sliced into french-fry style pieces with a Vadalia Onion Slicer. The pieces were put in a blender cup, nylon slipper sock stretched over, and contents shaken into the sock. Sample bags were put on black flats over plasticized paper and placed back in 40F cooler. When all samples were prepared, they were taken out again for weighing. They were then put into a warm air dryer at 130F until weight was stable. Dry/fresh weights was the calculutation for % dry matter. Figures usually represent two replications from separate field plots.

METHOD: Visual Examination. CONDITIONS: Greenhouse. METHOD NARR: Approximately 500 seeds were sown into 32 x 48 cm plastic flats from 120 populations of adg. Seedlings were grown for about six weeks in the greenhouse, after which time the dwarf phenotypes were clearly distinguishable. Dwarf and total numbers of seedlings were counted for each population. RESULTS NARR: There were dwarfs detected in fourteen of the 120 populations. Ten of the eleven populations from Mexico had dwarfs. The highest frequency (28%) of dwarfs came from a population from Colombia (PI 243364).

Study Name: Resistance to Early Blight. Experiment Type: Greenhouse GREENHOUSE Study Year: 1985 Year started: 09/09/1985 Year ended: 02/25/1986 Comment: Plants were inoculated with A. solani artificially by sprayi ng the plants with the inoculum three times at two week inte rvals. Severity of early blight symptoms were rated from 0 to 5 and noted on each of the test accessions.

Study Name: Resistance to Early Blight. Experiment Type: Greenhouse GREENHOUSE Study Year: 1986 Year started: 09/09/1986 Year ended: 03/10/1987. Plants were inoculated by spraying them with Alternaria solani inoculum three times at two week intervals. A disease index (0-5) was calculated by multiplying the fraction of individuals with symptoms times the average severity of symptoms.

144 accessions representing 29 species were used in this assay to evaluate EB resistance in wild potato species. This assay uses auxin to promote senescence in detached leaves, which are inoculated with a conidial suspension of A. solani. After seedlings were transplanted to individual peat pots for about a month, the oldest healthy leaf was collected from each plant and the petiole was inserted into 0.5% agar containing 10.7 mM auxin (1-naphthalene acetic acid) and tetracycline at 10 ug/ml in a petri dish. Three leaves (from three different plants) were placed on a plate. The next day, a mister was used to apply a 47,000 CFU/ml conidial suspension of A. solani (potato isolate) to the upper surface of each leaf. Petri dishes were incubated under continuous fluorescent light at 27C. After 72 h, individual leaves were scored based on severity of lesion development, from 0 (no lesions) to 4 (severe symptoms). One week later, a second replication was performed using the same plants and an inoculums density of 48,000 CFU/ml. Again, the oldest healthy leaf was sampled. A third replication was carried out 1 week after that, using 43,000 CFU/ml inoculum. The mean score for the three replications was calculated - mean scores of less than 1 were considered to have strong resistance.

Study Name: Resistance to Early Blight. Experiment Type: Field FIELD Study Year: 1985 Year started: 04/11/1985 Year ended: 09/24/1985. Four week old seedlings were planted to the field. Every third row was planted alternately to BelRus or Katahdin. The BelRus and Katahdin rows were inoculated about five weeks after transplanting with Alternaria solani infected dry leaves. Defoliation ratings (0-6) were made on both replications.

METHOD: Visual Examination ; Body Count CONDITIONS: Field METHOD NARR: CPB evaluations were scored by noting the percent defoliation of plants in the field. The accessions were grouped according to mean evaluation and these grouer numbers 1-6. PLH and PFB scores were generated by vacuuming plot samples. The plants were also rated on size so that an adjustment could be made for this parameter. The insects present were counted and the adjustmentshe accessions into clusters 1-4 (PLH) and 1-5 (PFB).

Plants were grown to flowering stage and observations were taken on flower color.

Study Name: Flowering Abundance. Six plants per accession were planted in the field during the summer of 1992. Each accession was compared to the other accessions within the species group and was given a flowering score (0-no flowers to 5-most flowering with species group).

Study Name: Flowering Abundance. Six plants per accession were planted in the field during the summer of 1994. Each accession was compared to the other accessions within the species group and was given a flowering score (0-no flowers to 5-most flowering with species group).

Study Name: Flowering Abundance. Six plants per accession were planted in the field during the summer of 1995. Each accession was compared to the other accessions within the species group and was given a flowering score (0-no flowers to 5-most flowering with species group).

Study Name: Flowering Abundance. Six plants per accession were planted in the field during the summer of 1996. Each accession was compared to the other accessions within the species group and was given a flowering score (0-no flowers to 5-most flowering with species group).

Study Name: Flowering Abundance. Six plants per accession were planted in the field during the summer of 1997. Each accession was compared to the other accessions within the species group and was given a flowering score (0-no flowers to 5-most flowering with species group).

Study Name: Flowering Abundance. Six plants per accession were planted in the field during the summer of 1998. Each accession was compared to the other acessions within the species group and was given a flowering score (0 - no flowers to 5 - most flowering within species group).

Study Name: Frost tolerance Experiment Type: FIELD FIELD Study Year: 1992 Year started: 05/06/1992 Year ended: 10/28/1992. The evaluation consisted of 2,625 accessions which were planted in the field in four hill plots. Accessions received frost scores (0-6) which were based on the amount of frost damage incurred by the plants. Accessions were scored twice, once after the first two light frosts, and then again after a more substantial frost. An average of these two scores was computed.

METHOD: Ion Leakage CONDITIONS: Green House - 14h light at 18-24C METHOD NARR: Frost tolerance was tested using the electrolyte leakage test of Sukumaran & Weiser, 1972. Sixty days after transplanting, fully expanded terminal le1C per hour from -2C to -6C. LT50 values were determined. Stomatal indenx was also determined. Tbr x cmm hybrids were also examined. RESULTS NARR: The estimated LT50 of cmm is -5.3 and tbr is 1.2. Hybrids were more rese were very close to the cmm parent. The stomatal index of the upper leaf surface of cmm was 13% and tbr was 6%. AUTHOR EXPLANATION: The stomatal index is said to be correlated with frost hardiness, but such a correlation waanalyzed.

METHOD: Cold Acclimation CONDITIONS: Growth Chamber - 14h light at 20/18C and lowered to 4/2C for cold acclimation METHOD NARR: Leaflets were placed in a glycerol bath at zero degrees C for ion leakage tests. The temp of the gly gradually and leaflets were evaluated for injury at a variety of temperature points. Freezing injury was assessed by measuring ion leakage. The difference between nonacclimated (NA) and freezing tolerance afteracclimationn capacity (ACC). Parents (cmm & tbr) were evaluated in addition to their progeny. RESULTS NARR: The results reported focus on the segregation of traits (NA and ACC) seen in progeny of the parental cross. The authors discusetween freezing tolerance and agronomic traits. AUTHOR EXPLANATION: This study demonstrated that it is feasible to combine high levels of freezing tolerance from cmm with high tuber yield and specific gravity.

METHOD: Ion Leakage CONDITIONS: Biotron - 14h light at 18-20C or 2-4C METHOD NARR: Freezing injury was measured by ion leakage in acclimated and unacclimated samples. A glycol bath was used to chill leaf samples by lowering the For chloroplast analysis total DNA was isolated, digested, and blotted onto a membrane. Petunia probes were used to distinguish the chloroplast contribution of tbr and cmm in progeny. RESULTS NARR: All species showed ane with acclimation. In somatic hybrids between tbr and brd, little of the acclimation ability from brd was expressed. In somatic hybrids between tbr and cmm the acclimation ability was intermediate to the two parents. AUTHORybrids, the sensitive-to-hardy genomic ratio could be an important determinant in the expression of acclimation vs. nonacclimation.

METHOD: Physical Measurement METHOD NARR: All plants were grown initially at 20/16C day/night temperature with 8h daylength and a photosynthetic photon flux density of 150 umol m-2 s-1. After 4 weeks, some of the plants were harve transferred to 12/9C or 5/2C temperature regimes with the other parameters stying the same. Plants were grown at these temperatures long enough to harvest leaflets that had developed fully under these conditions. Physicalmeasured, along with oxygen evolution and dark respiration. RESULTS NARR: It is possible to detect the primary injury of photoinhibition in cmm at temps as high as 12C. Much of the increase in leaf thickness was due to the iade layer. There were no significant differences in light saturated CO2-saturated O2 evolution or in dark respiration. AUTHOR EXPLANATION: Data suggest that there were an increased number of damaged PSII centers in the cold-acclimaes on the reducing side of QA may be sensitive to growth temperature. Leaves developed at chilling temperatures have a reduced capacity to utilize available light energy. Cmm is unable to alter its susceptibility to photon at 12/9C and 5/2C. These results support the idea that cmm exhibits properties that are typically associated with chilling sensitive rather than freezing tolerant plant species.

METHOD: Ion Leakage CONDITIONS: Biotron - 14h light at 18-20C or 2-4C with 70% RH METHOD NARR: Freezing tolerance was determined by measuring ion leakage following several freezing temperatures. The experiment also included extron of total and heat-stable proteins, lactate dehydrogenase cryoprotective assay and detection of dehydrin by Western blotting. RESULTS NARR: The concentration of heat-stable proteins increased following cold acclimation.elationship was found between heat-stable protein concentrations and nonacclimated (NARFT), acclimated (ACRFT) relative freezing tolerance and acclimation capacity (ACC). Except for S. sanctae rosea, dehydrin increased markedly. There appeared to be no systematic relationship of dehydrin expression with NARFT, ACRFT and ACC. AUTHOR EXPLANATION: The LDH cryoprotection study indicates that other heat-stable proteins (HSP) or components may be important facerance. HSP increase in tbr and cph may be a general stress response. It does not appear that dehydrin alone can explain the range of freezing tolerances in these materials. Cmm had the highest ACC and demonstrated thebehavior of the HSP. The quantitative increase in HSP during cold acclimation may not be responsible for the quantitative changes in freezing tolerance following cold acclimation.

METHOD: Content Assay CONDITIONS: Green House - 14h light at 18-20C or 2-4C METHOD NARR: Methods included the following procedures: preparation of the plasma membrane, protein concentration assay, lipid extraction, polar lipid factionation of total lipids, isolation and analysis of free sterols, glycolipids, phospholipids and fatty acid analysis. RESULTS NARR: Cold acclimation treatment resulted in an increased freeze tolerance from -4.5 to -9C inn tbr. Leaf plasma membrane lipids of cmm and tbr showed qualitative similarity but differed in quantitative respects. Acclimating cmm showed several plasma membrane lipid changes that did not occur in freezing-sensitive non-a in phospholipid content appears to be associated with increased freezing tolerance following acclimation in cmm. AUTHOR EXPLANATION: Comparing the plasma membrane from leaves of non-acclimated plants, a lower sterol-to-phospholipidportion of acylated steryl glycoside, and a lower proportion of free sterol were evident in cmm and may be related to greater freezing tolerance. These results suggest that the differences in freezing tolerance in the non to increase freezing tolerance during cold acclimation cannot be explained by the same biochemical and/or genetic mechanisms.

METHOD: Gene assay CONDITIONS: Growth Chamber - 14h light at 20-15C and 4C for cold acclimation METHOD NARR: Plantlets were grown in vitro at 20/15C and at 4C. The plantlets grown at 4C were deacclimated for 3 days at the warmeras collected from 8-day old plantlets of the control culture and those growing at 4C for 0, 2, 4, 6, 8, 10, 12 days (and deacclimated). Freezing tolerance was assessed by lowering temp. in increments of 2C from -1C down to -leachate was measured. Freezing tolerance was expressed as the temp. which caused 50% ion leakage. The mRNA was isolated and observed for changes associated with decreasing temperatures. RESULTS NARR: Most lines were fully. The hardened plants showed more resistance to freezing than the unhardened controls. Deacclimation caused a decrease in resistance compared to hardened, but still more resistant than controls. Many translation products increased ireatment. Three new products appeared in cold acclimated plants. Most of the changes appeared after 2 days at 4C and remained through day 10. AUTHOR EXPLANATION: Fewer changes in translation products of the less resiss are not active in this line. The increase in frost resistance during cold acclimation was correlated with the changes in translatable mRNA.

METHOD: Chemical Assay CONDITIONS: Growth Chamber - 14h light at 18-22C or 2-4C METHOD NARR: Five-week-old plants were subjected to 10 days of cold acclimation. Cold hardiness was measured by an electrical conductivity test. Th that caused a 50% loss of total leachate was designated as the killing temperature. Abscisic Acid (ABA) was extracted and purified and immunoassay was performed. A commercial EIA kit was purchased and the suppliers protoco Elevated ABA level does not have to exist at time of full hardiness development. Under salt stress there is one large transitory increase of ABA in contrast to the one or two small increases seen under cold stress. AUTHOR EXt show any interrelationship in the levels of free and conjugated ABA during potato cold acclimation, suggesting that conjugated ABA is not a source of the transitory increases of free ABA. Conjugated ABA is also not a major catabolitato during cold acclimation.

METHOD: Chemical Assay CONDITIONS: Growth Chamber - 14h light at 18-22C or 2-4C METHOD NARR: Five-week-old plants were subjected to 2-10 days of cold acclimation. Cycloheximide (CHI) was added to the culture medium. In additionlled methionine was added to the medium at approx. 3 hr. intervals. Cold hardiness was measured by an electrical conductivity test. The freezing temperature that caused a 50% loss of total leachate was designated as the kilcid (ABA) was extracted and purified and immunoassay was performed. Protein concentration was measured by a BCA protein assay kit. The incorporation rate of radioactivity in soluble protein fraction per gram fresh weight leafULTS NARR: The 1-day pretreatment with CHI resulted in less hardy plantlets. The 6hr-pretreatment with CHI resulted in full blockage of cold hardiness development. Return to CHI-free medium allowed hardiness to -8.3C. Initiation or 3 days of cold acclimation allowed plantlets to remain hardy at -8.3C. AUTHOR EXPLANATION: Cycloheximide is an inhibitor of cytoplasmic protein synthesis. Increase in free ABA during cold acclimation can be blocked i Theory 1: CHI blocks increase in ABA which is required as a trigger for synthesis of new proteins involved in cold acclimation. Theory 2: CHI blocks synthesis of cold acclimation proteins directly. Previous work sA increase is regulated by newly synthesized proteins in response to low temperatures, and the subsequent development of cold hardiness depends on ABA-mediated gene expression.

METHOD: Salt Stress CONDITIONS: Growth Chamber - 14h light at 18-22C or 2-4C METHOD NARR: NaCl solution was added to the culture medium of five-week-old plantlets. Three groups were grown under varying conditions: temperate fors, temperate for 7 days with ABA added. Cold hardiness was measured by an electrical conductivity test. The freezing temperature that caused a 50% loss of total leachate was designated as the killing temperature. Abscisicrified and immunoassay was performed. After 1-day of salt treatment, and 3 days of cold- and ABA-treatments, 2 leaflets per sample were radioactively labeled on the abaxial surface of the leaflets. Proteins were extracted and q ABA treatment increased the cold hardines by about 6C by the fifth day. Salt treatment in liquid culture medium resulted in a 3C increase in cold hardiness which is less than both the ABA- and cold-treatments. The development of colstress occurred immediately after the transitory increase in free ABA. Salt treatment resulted in alterations of protein synthesis pattern in the leaf tissue. AUTHOR EXPLANATION: Results suggest that the salt-induced sive proteins is associated with the induction of cold hardiness of the plantlets by salt stress. Results also suggest that these 3 proteins may play a major role in the acquisition of cold hardiness in response to co

METHOD: Ion Leakage CONDITIONS: Green House - 18h light at 15-20C METHOD NARR: Plants were cold acclimated in a growth chamber either at 2-4C or 1-2C in a 14h photoperiod. High and low light intensities were used. Temperature w 2C per hour from 10C to either non-freezing (2C) or freezing (-3C) night frost. Molecular tests were used to examine induction of the Scgst1 gene, which codes for glutathione S-transferase, and it's activity levels. RESULTture reglated GST was isolated from cmm. A single copy of the gene (Scgst 1) was found in both cmm and tbr. Accumulation of the transcript was seen in cmm but not tbr under excess light/low temperature conditions. Cmm x tbr h levels of accumulation. The association between frezing tolerance and Scgst 1 transcript was lost in S1 genotypes. AUTHOR EXPLANATION: Adaptation to low temperature is based on numerous mechanisms.

METHOD: Light Stress CONDITIONS: Lab - 18h light at 70% RH METHOD NARR: A 2-compartment chamber for exposure of previously frozen leaf disks to high-light intensity at low temperature was constructed. A single plant of cmm was p temp was above freezing, and left out overnight with freezing temps and allowed to thaw the next morning. Tissue temp, light energy levels and air temp were measured. Freeze-Thaw treatments were conducted on acl in the labe. Post-thaw light stress was measured in acl through photosynthesis and respiration. RESULTS NARR: Irreversible damage was usually indicated when ion leakage >30% of total ions present in cell. The sharp increase in ion leuggests the difference between cell survival and death. While the various freezing stresses and post-thaw treatments had no effect on chlorophyll content of tissue from acl, photosynthetic function was consistently and markedly more dce of light than in the paired dark-held tissues. Light-limited and light-saturated photosynthesis were both eliminated at -5C. The effects on respiration were limited. AUTHOR EXPLANATION: Photosynthesis was the mostfreezing stress, followed by ion leakage and then respiration. The results presented may help explain why freezing injury is not always immediately apparent. If freezing tolerance and tolerance of light stress are ince in the absence of light may lead to erroneaous conclusions about the relative frost-tolerance of plant materials.

METHOD: Light Stress CONDITIONS: Lab - 14h light at 15/20C with 55-70% RH METHOD NARR: Three different experiments were conducted. #1: Simulation of natural freeze thaw stress. #2: Comparison of protocols (Slow, Fast and Flash Fg). #3: Comparison of two freezing rates on a single leaflet (Slow and Fast Freeze). Photosynthesis, respiration and ion leakage (membrane permeability) were measured. RESULTS NARR: Respiration (R) photosynthesis (PS) aniffered markedly in their sensitivity to freeze-thaw stress. Various freeze-thaw protocols had dramatically different effects on R, PS and MP while min. tissue temps remained steady. PS was much more sensitive to freeze-thaw s showed the largest decline while supercooling had no inhibition. Chloroplast, mitochondrial and cell membrane function differ in their sensitivity to realistic freeze-thaw stress. The conclusions are highly dependent on the freeze-tSlight increases in freezing rates above those normally occuring in nature can mean the difference between cell survival and death. AUTHOR EXPLANATION: Climatological data demonstrates that air cooling rates in the subz 2C/hour even during extreme drops in temp. in Wisconsin. Stress associated with ice formation, not simply tissue temp. is an important factor in freezing injury.

METHOD: Light Stress CONDITIONS: Lab - 12h light at 18C with 70-80% RH METHOD NARR: Plants initially grown at 18C were transferred to either 12 or 24C for 4 weeks. Leaf tissue was the subjected to low temp and either high lightptake was measured in the dark chamber followed by light-limited and light-saturated Oxygen evolution. Chl was extacted and quantitated. RESULTS NARR: Acclimation of tbr to lower temp with constant light results in the inetic tissue to tolerate high light stress at low temps. Cmm has a much greater tolerance to high light stress at chilling than does tbr after growth at 24C. AUTHOR EXPLANATION: Plant adaptations which would reduce light trapse the capacity for light energy utilization would appear to provide greater protection of the photosynthetic apparatus during sudden changes in the light and/or temperature environment. This work shows that light limited photosynthesve indicator of initial photoinhibitory injuy than is light-saturated photosynthesis.

METHOD: Inheritance CONDITIONS: Biotron - 14h light at 18-20C and 70% RH or 2-4C METHOD NARR: Freezing tolerance was determined by gradually lowering the temperature of a cooling bath and submerging tubes containing excised leaflwas assessed by measurement of ion leakage. Relative freezing tolerance was determined from the midpoint of the maximum and minimum ion leakage vales obtained for each genotype. RESULTS NARR: The mean nonacclimated RFT ofto that of the cph parent than that of the cmm parent. Similarly, acclimation capacity of the F1 population was closer to that of the cph parent. These two traits were not significantly correlated , suggesting independent genes. Additive-dominance is adequate to explain acclimation capacity but not nonacclimated freezing tolerance. AUTHOR EXPLANATION: The distributions of the backcross progenies support the conclusion that nonacclimated freezing toleranapacity are controlled by relatively few genes, since backcross distributions show near recovery of parental phenotypes for nonacclimated freezing tolerance and full recovery for acclimation capacity. During active growtht survival depends on the nonacc. freezing tolerance. During cold acclimation conditions in fall, growth usually slows and the plant goes in to dormancy.

METHOD: Ion Leakage CONDITIONS: Green House - 14h light at 14-18C METHOD NARR: Leaflet and callus tissue were evaluated for frost tolerance. Freezing was achieved by both submersion and non-submersion techniques. Frost damage oby electrolyte leakage conductivity. The temperature resulting in 50% viability reduction was recorded. Comparison of frost tolerance with other biochemical factors (Amino acids, Proline and Electrolytes) was also determinerost tolerance in acl is associated with AA contents and electrolyte levels, and to a lesser extent Proline levels, indicating additional frost tolerance mechanisms may be involved. Acl is the only species that showed sig. higr in both callus and cell suspensions. Mga & cmm were more tolerant to frost at the plant level, while plt was more tolerant as callus tissue. AUTHOR EXPLANATION: Submerged freezing causes more damage to cells than non-submerged f the frost tolerance measures. Frost tolerance of some wild Solanum species is poorly refelcted in frost-killing temperature of cell culture, whether as callus or as suspensions.

METHOD: Ion Leakage CONDITIONS: Green House - 14h light at 20C METHOD NARR: Ten-week-old plants were divided into one of two groups. One group was used to measure frost tolerance without cold acclimation. The other group was moh light at 2C) for 2 weeks. Freezing injury was estimated by the ion leakage method. LT50 is the temperature at which 50% of the cells were killed. A cross was made and progeny were tested similarly. RESULTS NARR: There0 between nonacclimated and acclimated plants of a particular genotype, and also between individual genotypes. AUTHOR EXPLANATION: These results support the conclusions that frost hardiness and cold acclimation potential areontrol of relatively few genes. An additive-dominance model adequately explains the gene action of frost hardiness and cold acclimation. This study used LT50 as a measure while others have used acclimation capacity. These quantities

METHOD: Chemical Assay CONDITIONS: Field METHOD NARR: Two treatments were used. Calcium nitrate was used as a source of supplemental calcium which was applied 3 times. The treatment without extra calcium recieved an equivalentthe form of ammonium nitrate on the same three dates. Measurements of the calcium concentration in leaves were made using an atomic absorption spectrophotometer. Temperature was monitored throughout the field. RESULTS NARR frost were detected. There were highly significant differences among the accessions for both their ability to accumulate calcium and their frost tolerance. In general (but not always), a drop in frost score (increase in surviation of extra calcium. Frost damage was scored on a 1-6 scale with 1=no damage and 6=plant killed. AUTHOR EXPLANATION: The different response observed among the accessions suggests that even though some accessions are able to accy may lack the ability to benefit from the added calcium. Both sensitive and hardy species responded positively to supplemental calcium.

METHOD: Ion Leakage CONDITIONS: Biotron - 14h light at 18-20C or 2-4C with 70% RH METHOD NARR: Freezing tolerance was measured by gradually lowering leaflet temperature in a glycol bath and measuring ion leakage. Measurements weion leakage curve. Rates of deacclimation were also measured. RESULTS NARR: Four types of acclimators were observed: 1- early acclimators that showed 40-50% acclimation within days 1-3; 2- late acclimators gained the majofter at least 6 days of cold treatment; 3- progressive acclimators showed a steady increase of cold acclimation over time; 4- nonacclimators showed no acclimation ability. The extent of deacclimation during 12h at 18C varied frdeacclimators to high (over 60%) in rapid deacclimators. AUTHOR EXPLANATION: Rates of cold acclimation and deacclimation are not necessarily related to the acclimation capacity of the species. Ideally one would want to have rapid adeacclimation incorporated into the same plant for breeding purposes. Mga subsp. tor is the best choice of those tested.

Total foliar glycoalkaloid levels were determined by taking random samples consisting of 20-30 midlevel leaves from 4-6 sibs and boiling them in ethanol acidified with glacial acetic acid to extract the glycoalkaloids. The extracts were filtered out and analyzed by the TLC method to determine which glycoalkaloids were present and the GLC method to determine the amount and type of aglycone(s).

METHOD: Glycoalkaloid assay CONDITIONS: Green House - 16h light at 27C/20C day/night METHOD NARR: Glycoalkyloids were separated by HPTLC. Co-chromatography with standards and reverse phase HPLC were used to confirm the identificevelopment times varied to distinguish extracts present in high vs. low concentrations. RESULTS NARR: The new technique being tested was not reliable in detecting solanine or leptinine II. Leptine I was readily detected.458313 contained 420mg/100g of leptine I + II while chc 320287 contained 160mg/100g of the leptines. AUTHOR EXPLANATION: Field and laboratory tests show that leptine levels below 20mg% only weakly deter CPB, or not at all. Tce for setting the detection level at 20mg% or above. Using the TLC method, 80 samples per day can be processed compared to 10 for GLC and 4 for HPLC.

METHOD: Glycoalkaloid Assay METHOD NARR: Individual glycoalkaloids were characterized by TLC and comparisons made with standards. Aglycones were characterized by TLC and GLC as described in Sinden et al 1980. Total glycoalkaloids a titration method, see Fitzpatrick & Osman 1974. RESULTS NARR: Authors discuss taxonomy and geographical considerations. Wild species have higher levels of TGA than cultigens and conspecific weeds. Glycoalkaloid patterre closer across species lines than within mga alone and show distinct geographical patterns. Peruvian species assigned to this series stand out chemotaxonomically. Sgr has a unique glycoalkaloid pattern. AUTHOR EXPLANATION: collected and GH-grown material and between large and small tubers make comparisons using TGA content difficult.

METHOD: Glycoalkaloid Assay METHOD NARR: Extraction and analysis procedures for the identification of ammonia precipitable glycoalkyloids by thin-layer and gas chromatography and the determination of TGA content by titration were& Osman 1986. RESULTS NARR: Glycoalkaloids in potatoes are generally regarded as toxic at 20mg/100g or greater, and unpalatable to humans. Most of the wild tubers used in the study are potentially toxic and unplalatable. Llycoalkaloids in Mexican cph and ehr is consistent with the suggestion that nontoxic, edible potatoes exist in the wild. Exploitation of buk would require little or no selection for gycoalkaloid content due to moderately low le Authors discuss origins of domesticated potato considering TGA content of likely progenitor species.

METHOD: Glycoalkaloid Assay CONDITIONS: Green House and Tissue Culture METHOD NARR: A new procedure was developed that combines the extraction and hydrolysis of glykoalkaloids into a single step and uses capillary GC to quantita glykoalkaloid (SGA) aglycons from leaves and tubers. This process avoids ammonia precipitation and uses tomatine as an internal standard. RESULTS NARR: Chc leaves contained higher levels of alkaloids than tubers. In GHnidine 54%, leptinidine 36% and solanidine 10%. The trend differed in plant grown in vitro with solanidine 66%, acetylleptinidine 20% and leptinidine 14%. Acetylleptinidine was not detected in chc tubers. AUTHOR EXPLANATION:uantitatively influenced by the environment. The choice of tomatine as an internal standard was suitable for this experiment because, in the case of chc, it meets the 5 major criteria used to define a good internal standard. In futurrd must be determined by considering which glykoalkaloids are likely to be found for the species being investigated.

METHOD: Leptine Assay CONDITIONS: Green House - 16h light METHOD NARR: F1, interF1 and backcross families were assayed forTGA and foliar leptine production. Crosses were made between high (>62%) and low (<17%) producers of lepties. Specific glycoalkaloids were quantified by analytical HPLC. RESULTS NARR: Based on F1 segregation, it appears that high leptine proportion is controlled by a recessive gene. The presence of leptine in all hybrids ofl effect of the tubersoum parent on the amounts and proportions of leptines in the hybrids, indicates polygenic control by dominant gene(s). Unexpected segregation ratios were found. The F1 generation analysis indicates homozye the interF1 and backcross generations indicate a more complex inheritance model which involves a second major gene. AUTHOR EXPLANATION: Light is known to affect glycoalkaloid levels so all plants recieved supplemental light to 16h

METHOD: Glycoalkaloid Assay CONDITIONS: Green House - 16h light METHOD NARR: Quantification of glycoalkaloids was performed by analytical HPLC with a-solanine as the chromatographic standard. TLC was used to futher identify thosed from known glycoalkaloids. To evaluate the effect of altitude, accessions were divided into discrete elevational classes and statistically analyzed. RESULTS NARR: There was a strong correlation between and within leptie also positive correlations between solanine and chaconine, which were found in all accessions tested. A significant trend was observed between TGA and elevation, with TGA decreasing with increasing elevation. Concentrations, chaconine and TGA, but not of leptines or leptinines were negatively correlated with altitude. AUTHOR EXPLANATION: The inheritance of genes for leptine synthesis is complex, having quantitative aspects and possibly involving envirc interactions. Like solanine and chaconine, leptinine only weekly deters feeding by CPB. The likelihood that solanine and chaconine function as allelochemicals, in planta, is rather high.

METHOD: Glycoalkaloid Assay CONDITIONS: Field METHOD NARR: Glycoalk content was determined using the column and HPLC analytical method of Sinden et al 1986. Additionally, high-performance thin-layer chromatography was used on thLTS NARR: The only glycoalkaloids detected by both HPLC and TLC in chc were a-Solanine and a-Chaconine. F2 and F4 populations had similar sol, chac and TGA mean contents. Both populations had signifcantly lower mean contehigher contents than tbr. Chc produced 7 times more TGA than tbr, while the F2 mean TGA content was only 2.4 times higher than tbr and 3-fold lower than chc. The chac:sol ratios in F2 were closer to the tbr parent. AUTHOR EXPprogeny between the chc x tbr cross indicates a dominance effect of the tbr gene for lower glycoalkaloid synthesis in the hybrid population. Even after 2 backcrosses to tbr, there were still some effects of the chc genes on foliage GA

METHOD: Glycoalkaloid Assay CONDITIONS: Field METHOD NARR: Glycoalkaloid content was determined using the column and HPLC analytical method of Sinden et al 1986. Additionally, high-performance thin-layer chromatography was used RESULTS NARR: The average weight of the 1992 chc sample tubers were significantly lower than in all other populations. The F2 and F4 population tubers were significantly smaller than those of the tbr parent. In 1992 chcne content compared to tbr. Mean sol contents in F2 and F4 pops. were significantly lower than chc but significantly higher than tbr. The mean chac:sol ratios for chc were lower than other populations. TGA of chc consisted one. AUTHOR EXPLANATION: This is a companion paper to Sanford et al 1994 and the same plants were used for both papers. When comparing the the foliage and tuber results obtained, the correlation coefficients were not significant. Thmplications of the fact that tuber size plays a role in the results obtained.

METHOD: Glycoalkaloid Assay CONDITIONS: Green House METHOD NARR: Aglycones were separated on TLC silica gel plates. CPB larval survival tests were also conducted. The plants were grown in replicate and those accessions showingpositions were selected for further experiments. PI320287 is represented by two genotypes that give different results. RESULTS NARR: Spatial patterns of glycoalkaloids were investigated. Leaves and petioles expressed Sole level. The stem produced the same types but to a lesser extent. Tubers contained only Sol and no leptines were detected. There were significant differences in larval survival between the various accessions. AUTHOR EXPLANATe that leptine synthesis may be associated with a certain rare chromosomal rearrangement such as transposition. The CPB larval survival test indicates that there is a substantial level of resistance in chc against this insect, althougsfully coped with the glycoalkaloids metabolically. The presence of sol and OH-sol in all Ac-sol containing plants suggests that the Ac-sol is synthesized via OH-sol from sol.

METHOD: Visual Examination ; Body Count CONDITIONS: Field METHOD NARR: The mean number of aphids (GPAPHID and PAPHID) per plant was calculated for 1 or more trials per accession. Species with a mean insect score less than the ovtandard deviation were considered resistant, and species with a mean score higher than the overall mean score plus one standard deviation were considered susceptible.

METHOD: Life Cycle CONDITIONS: Green House - 16h light at 20-26C, RH 60-90% METHOD NARR: Plants were grown in a GH and leaves were removed as needed for each of the different assays. Feeding behavior of GPA was examined with anechnique. The number of probes, preprobe time and total probing time were recorded. Survivorship and fecundity data were obtained on intact leaflets by measuring length of stadia, adult life span, age at first reproduction, and total reproduction. Droplets of type B trichomes were removed and the same life cycle parameters as above were collected. Rate of type B droplet regeneration was determined. Phenolic oxidation activity in trichomes was d Densities of both types of glandular trichomes were significantly less on ncd than on ber. Type B droplets of ncd were significantly larger than those of ber. Regeneration of droplets, after removal, to original dimensions by day 52 was nearly 100%. Preprobe time on ncd was significantly delayed but total feeding time did not differ from tbr. Net replacement rate of GPA was 1.3 on ncd, 5.2 on tbr and 8.2 on ber473334 and there was no reproductions intermediate to tbr and ber310927. Fecundity and the mean number of offspring produced per aphid per day was greater on ncd than tbr. Length of developmental period and survival increased with removal of type B exation activity of ncd was similar to tbr (low) while that of ber was high. AUTHOR EXPLANATION: These findings demonstrate that type B glandular trichomes play an important role in the resistance of ncd to GPA.d survivorship on ncd reflects stress associated with immobilization and struggling in the encounter with very large droplets of extrem

Myzus persicae and Ma. euphorbiae were reared on S. tuberosum cv. Desiree plants in environmental chambers. For each aphid species, at least 50 nymphs younger than 24 h were transferred in microcages clipped on the lower face of a potato leaf at the third or fourth level from the apex (10 plants with five nymphs per microcage). For each aphid species, two groups of five plants from the same accession or the standard were randomly placed in environmental chambers. Emerged adult aphids were each isolated in a microcage, and their demographic parameters were evaluated every third day during a period equivalent to their prereproductive period (Le Roux et al., 2004). Nymph survival, prereproductive period, that is the period of time from birth until onset of reproduction, adult survival and calculated daily fecundity were assessed for each accession. For each feeding assay, the intrinsic rate of natural increase was calculated.

METHOD: Test Diet METHOD NARR: Excised leaflets of ber were used in a choice test for female apterous aphids. The number of aphids present on the abaxial surface of the leaflets was counted at 30, 180 and 330 minutes after releasones carrying type A and B trichomes were least preferred. AUTHOR EXPLANATION: The observed behaviour was probably influenced by volatile compounds present in type B trichome exudate.

METHOD: Mortality CONDITIONS: Green House - 16h light METHOD NARR: Cuttings of field grown plants were grown in the GH and used to determine biological activity of type B droplets. The droplets were removed from one of a pair ofn ethanol for about 5 seconds. Aphids were caged with both dipped and undipped leaflets. The position of the aphids relative to the leaflet, whether or not they were in a feeding position and mortality were recorded. All ap exudate on tarsi. Biological activity of sucrose esters was tested by feeding aphids a sucrose solution through a membrane. In the first test the side of the membrane adjacent to the aphids was coated and in the second test,phids was coated. In both tests, settling and # of stylet sheaths were measured. RESULTS NARR: Ethanol dip had no effect on feeding or mortality. Removal of type B droplets increased the fraction of aphids feeding for 36 hr after t leaflets showed significantly higher mortality. Settling and probing behaviors were affected only when aphids were in physical contact with the sucrose esters. AUTHOR EXPLANATION: Despite the lack od toxicity, sucroseof settling and probing by aphids. Results suggest that contact with organs other than the stylets is required for behavioral activity which could be due to either chemosensory or tactile responses. Aphids were not

METHOD: Visual Examination CONDITIONS: Green House, Lab and Field. METHOD NARR: This paper is a result of a series of 39 experiments performed in many places, under varying conditions and with different insect sources, all of whaper but too numerous to mention here. In all experiments, data were recorded as mean number of GPA per plant. RESULTS NARR: Coefficients of variation (CV) were calculated for each accession across all 39 evaluations. Loence of stability of relative resistance across evaluations. Over all evaluations, relative resistance was consistant with results reported previously. Resistance indices were computed as a ratio of mean GPA per plant/averagehe 15 accessions common to all 39 evaluations. AUTHOR EXPLANATION: If GPA-resistant breeding lines were developed, they could be used widely and this resistance would prove stable.

METHOD: Feeding Behavior CONDITIONS: Green House METHOD NARR: The preference of M. persicae between etb and frn was checked, as was the preference for various parts of these plants. Electronic monitoring of the feeding behavioring a wire to the dorsum of the aphid and completing the circuit by pushing an electrode through the stem or petiole of the plant. RESULTS NARR: When the aphids were allowed to choose between etb and frd in the young stageered. In choice tests the aphids prefered frd over tbr, colonizing all parts of the plant. AUTHOR EXPLANATION: Resistance is linked to the physiological age of the plants with older plants becoming more susceptible. The precent leaves rather than mature leaves may be a response to high levels of soluble organic nitrogen in the phloem of growing or senescent parts of the plant. Also, the chemical contents, e.g. minerals, or compounds antibiotic to the aperence although there is currently little support for this idea.

Greening of the tuber skin is an undesirable defect. Tubers of 90 Solanum microdontum families represented by 12 individuals each were generated in the winter greenhouse in 2009-2010. These were evaluated in two trials of family bulks after four days of exposure to 200 ft candles of fluorescent white light at room temperature. This light intensity was similar to that measured in local grocery stores, and according to preliminary tests, was known to turn some microdontum tubers very green. A qualitative score of green (G) or white (W) was assigned to each tuber, but notes on shade of green were also made. Tubers of about 80 families were uniformly G or variable, with 10 families noted as mostly W (especially PI 595506 from Argentina). When nine families were selected for replicated follow-up testing on an individual clone basis, the results matched those of the bulk tuber trials, and there was virtually no variation within clone. Two replicates of about 65 G and 65 W individual tubers were selected from a variety of families, and planted in the summer greenhouse to create a new clonal generation of tubers. Those second generation tubers showed a response to illumination which was consistent with that of their mother tubers. In comparison, when 160 named tuberosum cultivars were illuminated in the same way, none from Europe or North America scored W. We are in the process of intermating G and W clones of microdontum to investigate the genetics and physiology of the trait, with a view to eventual breeding of strong greening resistance into cultivars.

METHOD: Life Cycle CONDITIONS: Growth Chamber - 12h light, 10-30% RH at 26C METHOD NARR: The following tests were conducted: Whitefly Trapping (on soaked vs unsoaked foliage), Population growth, Settling, Oviposition and Adult Em: Foliage was soaked to remove exudate, and these sample trapped significantly few whiteflies than the native leaf samples. Ber had more dead adults and far fewer larvae and adults in general compared to tbr. There was nopositioning or adult emergence. A small but significant difference in settling was observed with less settling on ber. AUTHOR EXPLANATION: Most of the resistance can probably be explained by physical interference since thereces in oviposition, developmental period and sex ratio. Differences in larval abundance were not a result of entrapment of larvae, which are small and relatively immobile, but from the smaller number of 2nd generation adults available

Study Name: Resistance to Meloidogyne Hapla Nematodes Experiment Type: Screenhouse SCREENHOUSE Study Year: 1985 Year started: 12/10/1985 Year ended: 04/01/1986. Eight week old seedlings were inoculated with 3000 second stage larvae. After three months, roots were examined for galls and an average gall rating (0-5) was calibrated for each accession.

Study Name: Resistance to Meloidogyne Hapla Nematodes Experiment Type: Screenhouse SCREENHOUSE Study Year: 1985 Year started: 03/08/1985 Year ended: 07/06/1987. One month old seedlings were inoculated with root-knot larvae to a concentration of 100 larvae per cc of soil. After 60 days, the root galls were counted and each accession was given a root rating (1-5). Colonies were then counted from a 100 cc sample of soil, and the log of the colony count was calculated (0-9.8).

Study Name: Resistance to Meloidogyne Hapla Nematodes Experiment Type: Screenhouse SCREENHOUSE Study Year: 1985 Year started: //1985 Year ended: 12/28/1986. Rooted cuttings were inoculated with 5000 eggs each. After a 60 day inoculation period, the plants were examined for root galls and given a root gall index (0-5). The roots were then examined for egg masses and were given an egg index rating (0-5). A reproduction rating (0-37.02) was also calculated and given to each accession.

Study Name: Tolerance to heat Experiment Type: Greenhouse GREENHOUSE Study Year: 1985 Year started: 05//1985 Year ended: 12/24/1985 Comment: The seedlings were grown in two houses, a hot house and a temperate house. The shoots from both replications were weighed and the weight ratio between hot and temperate grown plants were noted.

Study Name: Tolerance to heat Experiment Type: Greenhouse GREENHOUSE Study Year: 1986 Year started: 05//1986 Year ended: 12/12/1986 Comment: The plants were exposed to 50 degree centigrade temperatures and the heat killing time was noted. Heat killing time is the minutes needed at 50 degrees centigrade to cause death of leaf tissue.

METHOD: Life Cycle CONDITIONS: Green House - 14h light at 36-43C (hot) or 16-24C (temperate) METHOD NARR: In 1992 species were planted in GHs under either temperate or hot temperature regimens. At the start of the regimen, allt were removed from plants in both environments. Pollen was collected at the end of each of the following three weeks. This trial focused on pollen production which was scored subjectively and stained for viability. Anothe see separate entry. RESULTS NARR: Pollen production (Shed) was scored subjectively from 0-5 with 0=no pollen and 5=abundant pollen. Viability was assessed as % stained pollen (PSP) of 500 grain samples. Shed scores in them and high. Shed scores in the hot house were poor across all accessions. PSP scores in the temperate house were uniform and high with an average of 85%. In the hot house, the average was 33%.

METHOD: Life Cycle CONDITIONS: Green House - 14h light at 32-45C (hot) or 18-22C (temperate) METHOD NARR: See 1992 trial in separate entry. In the 1993 trial the heat regimens were initiated when flowering had generally become ae vents were adjusted each day so that night time minimum remained the same after initiation. This trial concentrated on flowering abundance and data was collected only once after three weeks. Pollen viability was scored. determined, and some plants were intermated within their experimental unit. Styles were collected after 3 days to determine pollen tube penetration. RESULTS NARR: Temperature significantly affected flowering. Species vary some actually showing an increase in flowering (mcd and cmm). Stylar examination provides useful information about relative pollen potency not revealed by shed or PSP. Selection for heat fertility is not a good indicator of vegetat AUTHOR EXPLANATION: Daily heat exposure was somewhat more severe and consistent in the 1993 experiment. The accessions with the best flowering did not necessarily have the best shed, and those with the best flowering,have the best pollen tube growth through the style. THis indicates that these factors need to be screened for individually.

METHOD: Life Cycle CONDITIONS: Field METHOD NARR: True Potato Seed (TPS) was planted in the field. When the plants were 78 days old, plant stands, tuber number, tuber weight and average tuber weight were assessed. Plants were aormance under hot conditions. Plants were rated for ground cover and vigor at 60 days. Tubers were harvested at maturity. The tests were conducted in 1984 and 1985. In 1984, 1488 accessions were tested and data is present. RESULTS NARR: There were no significant differences for ground cover or vigor among the 5 best entries. Tubers in general tended to be small (no line averaged over 10g) and many plants did not tuberize under these hot cond: Plants with ground cover would have cooler soil which favors tuberization. Large total yields instead of large tubers, along with tuber uniformity and quality, should be emphasized for most tuber production from TPS.

METHOD: Life Cycle CONDITIONS: Field METHOD NARR: True Potato Seed (TPS) was planted in the field. When the plants were 78 days old, plant stands, tuber number, tuber weight and average tuber weight were assessed. Plants were aormance under hot conditions. Plants were rated for ground cover and vigor at 60 days. Tubers were harvested at maturity. The tests were conducted in 1984 and 1985. In 1985, only the best 404 entries from the 1984 screenisented for the top 15. RESULTS NARR: There were no significant differences for ground cover or vigor among the 5 best entries. Tubers in general tended to be small (no line averaged over 10g) and many plants did not tuberize. AUTHOR EXPLANATION: Plants with ground cover would have cooler soil which favors tuberization. Large total yields instead of large tubers, along with tuber uniformity and quality, should be emphasized for most tuber production fr

METHOD: Life Cycle CONDITIONS: Growth Chamber - 18h light at either 33/25C (hot) or 20/10C (cool) METHOD NARR: Ten days after start of temperature regimen, plants were removed, separated into component parts, measured for leaf arnt weight. Additional plants were measured for CO2 flux. Efflux rates were measured to represent maintainance respiration. CO2 influx rates were made only on plants in the hot chamber. Chlorophyll flourescence measurement hot chamber after 1h in darkness at 30C. Initial, peak and terminal values were recorded. RESULTS NARR: Accessions with significantly smaller relative growth rate (RGR) & net assimilation rate (NAR) values than the controlpossess heat tolerance. Only occasionally did accessions significantly exceed the photosynthetic rate of control clones. Accessions with greater dry weight had greater investment in stem than leaf tissue, except for non-tuberosum clonvestment in stem dry weight. The chc accession exceeded the contol clones' value for RGR. Acl498066 and crc498116 were found to be heat tolerant. AUTHOR EXPLANATION: Measurements based on the disruption of PSII couldtolerance.

METHOD: Life Cycle CONDITIONS: Green House - 18h light at 35-42C in hot house (held at 30C overnight) and 30-40C in ventilated house (allowed to drop to 15-25C at night) METHOD NARR: Two plastic GH's were used. One was ventilateintained at a relatively high temperature. Plants were grown for 25-30 days under these conditions. Plants were assessed for vigor using a 1-9 scale (where 9 = absence of heat stress symptoms and 1 = complete necrosis) by tcolor, necrosis, chlorosis, leaf rolling, leaf angle, plant size and leaf size. The plants were cut at the soil line and weighed as an indication of shoot growth. Those plants showing some heat tolerance were transferred to shzation. Tuberization of bud cuttings was measured on a 1 to 5 scale where 5 was lowest induction and 1 was highest. RESULTS NARR: Accessions were deemed heat tolerant if an average vigor rating in the hot house >6, and either a fre or an average fresh weight in the hot house > the mean for all accessions grown in the hot house. Higher tuberization ratings indicate less induction to tuberize in the hot house. AUTHOR EXPLANATION: An accession withse and a high ratio of hot to ventilated fresh weight would be considered relatively insensitive to heat stress, whereas a high fresh weight but a low fresh weight ratio would indicate an accession with overall growthsitivity to heat stress. Induction of tuberization in leaves is not necessarily a reliable indicator of final tuber yield as tuberization can be inhibited by high soil temperature.

METHOD: Gas Exchange CONDITIONS: Growth Chamber - 14h light at 25/20C or 40/30C METHOD NARR: Control rates of photosynthesis were measured at 25C. Oxygen evolution was measured on fresh leaf discs at saturating CO2 and humidity electrode. Rates of oxygen evolution were normalized to the total Chl a + b content of each leaf disc. Chl a & b were measured immediately after rates of oxygen had been recorded, on the same leaf discs. Carbon fixaion wa steady state gas exchange system. Leaf temperature was determined by a thermocouple contacting the leaf. RESULTS NARR: Heat tolerant (HT) accessions showed higher maximal rates of oxygen evolution than heat sensitive (HS) aleaves of the HS accession exhibited less pronounced effects of heat treatment than did mature, fully expanded leaves on the same plant. All accessions showed lower stomatal conductance at 40C than for 25C controls. Changes in leaf C to Chl b ratios contributed significantly to the decline of PS performance in chc. AUTHOR EXPLANATION: Results suggest that Chl loss, reduced stomatal conductivity and accelerated senescence were the major factors accoosynthetic performance. HS may be a manifestation of accelerated senescence. It appears that CO2 availability is the major factor determining the difference in photosynthesis between HT and HS accessions at 40C. Vafactor in reduced CO2 fixation at 40C.

METHOD: Both ELISA and Visual Examination METHOD NARR: Wild Solanum species were mechanically inoculated with diluted sap of Nicotiana previously infected with the HeMV-W/H isolate. Visual inspection and ELISA were used to checkinoculation was also used. No specific ELISA values were given. RESULTS NARR: All 11 wild Solanum species were locally and systemically susceptible to the W/H isolate AUTHOR EXPLANATION: This data draws attention to thepresented by HeMV susceptible wild solanum species for both breeders and for finding resistant accessions.

METHOD: Both ELISA and Visual Examination METHOD NARR: Sto accessions were inoculated with PVY and HeMV. There were visual inspections every 7 days with ELISA at the end of weeks 3 and 6. No ELISA data is provided, only susceptimless plants were back-inoculated on indicator plants. RESULTS NARR: Eight of the sto accessions were found to be immune to PVY and 6 to HeMV. Three were immune t both viruses.

Sturgeon Bay 2001, Field inoculated, planted July 20, scored Oct 07, about 1/2 mile from Lake Michigan at 44? 45.151'N, x 87? 20.555'W, percent damage.

Sturgeon Bay 2002, Field inoculated, planted July 23, scored Oct 10, about 1/2 mile from Lake Michigan at 44? 45.151'N x 87? 20.555'W. Average severity scores.

Visual Examination CONDITIONS: Green House - Inoculation tent with RH above 90% and 18-25C METHOD NARR: Plants were placed in the inoculation tent and inoculated using a hand-held sprayer. Disease severity was estimated as the percentage of stem and leaf area with symptoms of late blight at 7 and 14 days after inoculation. Severity values were rated up to 4 weeks after inoculation. RESULTS NARR: Mexican accessions were more resistant to late blight than the Russian and South American accessions. There was a high range of variability found within all accessions and genotypes with good levels of resistance found in the Russian hybrids and SA species. AUTHOR EXPLANATION: While the Mexican accessions showed higher resistance, they are somewhat difficult to introgress into cultivated potato. There were genotypes of the South American and Russian Hybrid populations that showed moderate resistance. These specific genotypes may prove to be more useful in developing late-blight-resistant cultivars. Mcd, scr and ber were the best candidates for introgression.

Visual Examination CONDITIONS: Green House - Inoculation tent with RH above 90% and 18-25C METHOD NARR: Plants were placed in the inoculation tent and inoculated using a hand-held sprayer. Disease severity was estimated as the percentage of stem and leaf area with symptoms of late blight at 7 and 14 days after inoculation. Severity values were rated up to 4 weeks after inoculation. RESULTS NARR: Mexican accessions were more resistant to late blight than the Russian and South American accessions. There was a high range of variability found within all accessions and genotypes with good levels of resistance found in the Russian hybrids and SA species. AUTHOR EXPLANATION: While the Mexican accessions showed higher resistance, they are somewhat difficult to introgress into cultivated potato. There were genotypes of the South American and Russian Hybrid populations that showed moderate resistance. These specific genotypes may prove to be more useful in developing late-blight-resistant cultivars. Mcd, scr and ber were the best candidates for introgression.

The tuber inoculations were conducted over four dates (four replications). All tubers were surface sterilized in a 5% bleach solution, rinsed, and dried overnight prior to inoculation. Tubers were each inoculated by removing a 2.5 mm plug (5 mm depth), and placing a mycelia plug (mycelia down) in the hole, and covering with a dab of petroleum jelly. The US-8 P. infestans cultures were again provided by Dr. Kirk. Tubers were held in a humid box at 10C. The tubers were scored for late blight infection ~2 months after inoculation on a 0 ? 9 scale, with zero being no late blight infection; a tuber with 100% late blight coverage received a rating of nine.

164 S. demissum accessions were obtained from the US Potato Genebank and used in the late blight trial. They were transplanted to the field, and treated with a foliar inoculation of P. infestans US-23 genotype. Percent foliar infection of the plots were recorded at six dates, up to 50 days post inoculation. The percent foliar LB infection was used to calculate the RAUDPC. 148 accessions had no observed LB infection and would be considered LB resistant; 6 accessions had minor, late-season LB and would be considered to have reduced susceptibility to LB; and 5 accessions had moderate to significant LB infection and would be considered susceptible to LB. 5 accessions had No Data.

Inoculated field tests, 1998, AUDPC was scored on reps and a mean value was calculated.

Inoculated field tests, 1999, AUDPC was scored on reps and a mean value was calculated.

METHOD: Visual Examination CONDITIONS: Growth Chamber - 12h light, at 16C METHOD NARR: Plants were spray inoculated at about 6 weeks old. Race O and race 1.3.4.5 were each applied and evaluated seperately. Five days after inocuscored visually for percent necrotic tissue. Plants on which all the leaves were dead but having no stem lesions were rated as 70% necrotic. RESULTS NARR: Tbr was considered resistant while brd was sensitive. AUTHOR EXPL was generated and tested for resistance similarly to the parents. All of the progeny were significantly less necrotic than the brd parent for both races tested. However, the % necrosis was higher overall with race 1.3.4.5.

METHOD: Visual Examination CONDITIONS: Green House METHOD NARR: Comparisons were made of susceptible and resistance plants both in the field and in the GH. Representative results are given from the GH studies. An estimate of percent leaf infection by P. infestans was recorded. Infection rating of 0-9 as 5 day/8 day/12 day with 9 = no visible infection, 8 = <10%, 7 = 11-25%, 6 = 26-40%, 5 = 41-60%, 4 = 61-70%, 3 = 71-80%, 2 = 81-90%, 1 = >90%, 0 = 100%. RESULTS NARR: The hybrids generated were resistant to late blight. AUTHOR EXPLANATION: In addition to the parents, somatic hybrids were tested for resistance and characterized using RFLP and RAPD protocols. Resistance to P. infestans from blb seems to be more general than the race-specific resistance derived from dms.

METHOD: Visual Examination CONDITIONS: Green House METHOD NARR: Testing was done by inoculating circular leaf discs with sporangial suspensions of P. infestans and examining them 4-6 days later for evidence of sporulation. Afterntage of each leaf disc showing necrosis with sporulation was estimated. The test was repeated using leaves that were pretreated by soaking in water to remove water soluble residues. The residues were largely found to be su P. infestans sporulated more profusely on leaf discs of tbr than any ber clone. Those ber clones containing type B glandular tricomes showed considerably less sporulation than those without. Discs soaked to remove sucrose este intense sporulation than nonsoaked discs. Results of a sucrose ester dilution study support the conclusion that sucrose esters are the most likely source of fungitoxic activity. AUTHOR EXPLANATION: Accessions of ber containing tyd generate more interest as sources of novel fungitoxins and possibly provide potato breeders with means of resistance to late blight disease.

The screening on field resistance to LB was carried out in Pushkin res. Station by Methods of VER. (1982-2001). LB scale: 9 (resistant) to 1 (susceptible).

METHOD: Visual Examination CONDITIONS: Green House - 16h light METHOD NARR: Plants were grown from tubers. A single mature leaf 7-8 nodes down from the meristem was removed with a razor. The detached leaf was inoculated with P.6 and 11 days later. Disease severity index is based on percentage of leaf area affected: 0 = no symptoms, 1 = 0-5%, 3 = 6-25%, 5 = 26-50%, 7 = 51-75%, 9 = 76-100%. RESULTS NARR: Pnt was predominantly resistant with someotypes. Cph subsp. ehr were mostly susceptible except for 275215 which were resistant. Cph subsp. cph displayed a mix of phenotpes. AUTHOR EXPLANATION: Crosses were made to generate a family segregating for late-blight res late-blight resistance locus was mapped to chromosome 7.

Toluca, MEXICO, 1998, Percent Damage (mean of seedlings), mean of best quatrile and best and worst individual.

Toluca, MEXICO, 1999, Percent Damage (mean of seedlings), mean of best quatrile and best and worst individual.

Toluca, MEXICO, 2000, Percent Damage, mean of best quatrile and best and worst individual.

METHOD: Visual Examination CONDITIONS: Green House METHOD NARR: High humidity was maintained in the GH. Two experiments were carried out. In the first experiment, all clones were used, in the second clones were chosen for resislier test. First symptoms were observed 7 days after inoculation and readings wre taken 12 days after inoculation. Presence or absence of lesions was scored for each plant. RESULTS NARR: The results obtained in the GH coaves in the laboratory, showed an unacceptable degree of discrepancy. Mcd was the species with the highest number of resistant clones. The results were accession dependent for chc but not cmm or mcd. The reaction to the non-v accession dependent for mcd but not chc or cmm. AUTHOR EXPLANATION: The results obtained provide evidence of vertical resistance in some clones of cmm, mcd and chc.

METHOD: Visual Examination METHOD NARR: Detached leaves of each genotype were placed in petri dishes and inoculated with the 2 races of the fungus. Presence or absence of lesions was scored for each leaflet. RESULTS NARR: Thee GH compared to those of detached leaves in the laboratory, showed an unacceptable degree of discrepancy. Mcd was the species with the highest number of resistant clones. The results were accession dependent for chc but no the non-virulent race in the lab was accession dependent for mcd but not chc or cmm. AUTHOR EXPLANATION: The results obtained provide evidence of vertical resistance in some clones of cmm, mcd and chc.

METHOD: Visual Examination CONDITIONS: Green House and Field METHOD NARR: Inoculations were performed both in the GH and in field trials. In the GH whole plants were inoculated. Seven week-old, plants were evaluated 7 days aftntensity of foliage blight was measured by assessing overall amount of necrosis per plant. In the field trials plants were inoculated by natural infection. Once symptoms appeared, the percentage of leaf area affected was e RESULTS NARR: All plants scored 5-9 were defined as resistant while lower scores were considered susceptible. Chc showed a high frequency of resistant genotypes in both GH and Field. Results of individual accessions not pre: Accession specificity is a relevant factor in screening for horizontal resistance.

1996, Natural Infection, Percent Damage (mean of seedlings).

1997, Field inoculated percent damage, clone mean, mean of best quatrile, best and worst of multiple. Compared to checks: Libertas (R) = 43, Norkotah (S) = 100

1998, Field inoculated percent damage, clone mean, mean of best quatrile, best and worst of multiple. Compared to checks: Zarevo (R) = 90, Norkotah (S) = 100

METHOD: Visual Examination CONDITIONS: Green House - After inoculation, GH was shaded to maintain temp. range of 15-20C, and cool mist was applied. METHOD NARR: Accessions were grown in the GH through a series of 11 experiments.ed out in 2 phases. The first used plants grown from true seed. The second used plants grown from tubers of individual plants that had been selected for resistance during the first phase. The plants were spray inoculated ber transplanting to pots. After inoculation, conditions were maintained conducive to late blight growth. The proportion of total leaf area with symptoms was recorded for each individual plant at 2-day intervals beginning on thulation, for a total of 3-4 readings. RESULTS NARR: Resistance trends are given by species rather than individual accessions. Many species showed at least on individual with resistance. AUTHOR EXPLANATION: The GH evaluations mayt conditions to differentiate realistically between genotypes since 80-100% infection was reached in only 8 days rather than the typical 3-4 weeks. Validation in field trials is still required. Difference between accessiplained by genetic differences, sampling error, genetic drift or experimental error.

METHOD: Leaf disc bioassay CONDITIONS: Green House METHOD NARR: Four viruses, 1 fungus and 1 nematode were used to test for resistance. P. infestans resistance screening was a quantitative leaf disc bioassay according to Leona1992). Leaflets were collected from 12 week old plants. Inoculum from all available isolates was adjusted for sporangia and zoospore content and mixed. Leaf discs were inoculated with 40ul of suspension and incubated at 17 Resistant = <10% of leaf disc surface infected. Partially resistant = 10-20% of leaf disc surface infected. Accessions identified as resistant were retested to confirm resistance. RESULTS NARR: Over 70% of all evaluated are resistances. AUTHOR EXPLANATION: All tubers obtained from one accession were bulked due to limited tuber production under given conditions. Therefore, the results can not be generalized to the whole accession. Patterns of resis It is noted when the results obtained in this study do not match those of previous studies and explanations are offered.

Inoculated tuber LB results, 1999, Lesion length + width in mm, average of best quatrile of clones tested. COMPARED TO RUSSET BURBANK inoculated = 63.0 and Russet Burbank inoculated with water = 0.0.

METHOD: Visual Examination CONDITIONS: Growth Chamber - 16h light, 18-20C METHOD NARR: Plants were grown for 4 weeks before detaching a leaflet to be used immediately in screening test. Each isolate of P. infestans was applied s after inoculation the leaflets were examined with a dissecting scope to determine percentage of area affected and sporulation rating. RESULTS NARR: A 0-3 rating scale was used where 0 = no sporulation, 1 = light sporulati3 = heavy sporulation. Percent colonized = mean percentage leaflet necrotic and/or supporting sporulation. AUTHOR EXPLANATION: The presence of differential responses to isolates may indicate the presence of R-genes. Furthere the presence of hypersensitive flecks observed on susceptible leaflets. Heterogeneity within PIs was observed.

In our previous screening for resistance to late blight using a detached leaf assay, we identified the diploid wild type JAM1-4 (S. jamesii), which originated from the United States, was highly resistant to the super race strain 2013-18-306. In this study, we used potato tissue culture plants for live inoculation with P. infestans. The tissue culture plants of JAM1-4 (S. jamesii) were cultured in 30 ml of MS medium and grown for 4 weeks under the conditions with 16 h of light, 8 h of dark, light intensity of 2,000 lx, and temperature of 22°C. Then the 8 to 10 tissue culture plants of each bottle were inoculated with P. infestans or as control.

The artificial screening on resistance to tuber late blight was made in Polish Institute of Plant Acclimatization (IHAR, Nlochov) by Methods of IHAR (resistance to viruses was made in collaboration with Dr. M. Khrzhanovska) and in VIR greenhouses and laboratories and All-Russian Institute of Plant Industry. Pushkin, Saint-Petersburg. LB scale: 9 (resistant) to 1 (susceptible).

METHOD: Visual Examination ; Body Count CONDITIONS: Field METHOD NARR: CPB evaluations were scored by noting the percent defoliation of plants in the field. The accessions were grouped according to mean evaluation and these grouer numbers 1-6. PLH and PFB scores were generated by vacuuming plot samples. The plants were also rated on size so that an adjustment could be made for this parameter. The insects present were counted and the adjustmentshe accessions into clusters 1-4 (PLH) and 1-5 (PFB).

METHOD: Test Diet CONDITIONS: Lab METHOD NARR: Glycoalkaloids were isolated from ber and leptines from chc. Purity and quantity were determined by HPLC. Test diets were prepared with 3 different concentrations of glycoalkaloidsfhoppers during 72 hour test periods. Percent mortality on each diet was measured. RESULTS NARR: Major effects occured at the 0.09% and 0.27% concentrations, although considerable mortality occured on the solmargine and tcentration. At all concentrations, mortality was the greatest with tomatine in the diet. AUTHOR EXPLANATION: Other authors (Dahlman & Hibbs) have reported resistance to PLH using Leptine 1. The present authors speculate tharom chc only by the presence of an ester carbonyl group, a mistaken identification would account for the different resistance evaluations.

A population of the wild potato S. stoloniferum form fendleri (PI 660270) was collected as botanical seeds in the Santa Rita Mountains near Green Valley, Arizona, USA in fall 2010. Original seeds planted for multiplication at the genebank produced two plants with extra whorls of petals, sometimes fused with anthers, and, most remarkably, successive whorls of petals, anthers and carpels nested inside the primary carpel. This mutant was named Matryoshka after the similarly nested Russian dolls.

METHOD: Reproductive Efficiency CONDITIONS: Green House - 24C METHOD NARR: Two experiments were done. The first (GH) test determined reproductive efficiency through egg counts. When rooted cuttings were transplanted to pots, an000 M. chitwoodi eggs was pipetted into the soil. Plants were allowed to grow for 55 days before harvest. A reproductive efficiency value was determined using egg counts. The second (in vitro) test determined the host suitugh egg counts. See separate entry. AUTHOR EXPLANATION: There was sufficient correspondence between screening methods for Race 1 to promote the use of in vitro screening to identify resistance in a breeding program. The lac detracts from this view. As a result, determination of R factors by egg counts was the only criterion usable for host response.

METHOD: Reproductive Efficiency CONDITIONS: Lab - 21C METHOD NARR: Two experiments were done. The first (GH) test determined reproductive efficiency through egg counts. See separate entry. The second (in vitro) test determinedf the blb clones grown under sterile in vitro culture conditions. Roots were infected with hatched second-stage juveniles and allowed to grow for 55 days. The number of eggs was counted and used to generate a reproductive eNATION: There was sufficient correspondence between screening methods for Race 1 to promote the use of in vitro screening to identify resistance in a breeding program. The lack of concordance for Race 2 detracts from this vieion of R factors by egg counts was the only criterion usable for host response.

METHOD: Reproductive Efficiency CONDITIONS: Green House - 24C METHOD NARR: The object of the test was to determine reproductive efficiency through egg counts. When rooted cuttings were transplanted to pots, an aliquot containinggs was pipetted into the soil. Plants were allowed to grow for 55 days before harvest. A reproductive efficiency value was determined using egg counts. Crosses were made and F1 hybrids evaluated. RESULTS NARR: There wasaccessions. PI 161726 was resistant to M. chitwoodi growth for both races and used to produce hybrid progeny with tbr. AUTHOR EXPLANATION: Resistance to race 1 is not correlated with resistance to race 2 in inheritance tests.

METHOD: Reproductive Efficiency CONDITIONS: Green House and Field METHOD NARR: Tests of tuber resistance and reproductive efficiency to M. chitwoodi races 1 & 2, and M. hapla, were performed in microplots of 19L volume buckets pa. These micro plots were inoculated with 25,000 eggs and allowed to grow for 90-135 days until harvest. Egg counts were made and tuber damage was rated. Additionally, tests for reproductive efficiency were carried out in tTION: Analysis of the hybrids makes it appear that resistance to race 1 is inherited in a discrete fashion. Resistance appears to be a dominant character.

METHOD: Reproductive Efficiency CONDITIONS: Green House and Field METHOD NARR: In the GH tests # of nematodes and their development were monitored for 8 weeks. A reproductive factor was was calculated. Tuber tests were conducteubers were hand peeled and examined for infection. RESULTS NARR: Development of M. chitwoodi was delayed and only half of the infective nematodes established feeding sites and matured on resistant clones. Blb rarely produs. AUTHOR EXPLANATION: It was possible that a hypersensitive reaction was mainly responsible for the failure of M. chitwoodi to mature normally or deposit large numbers of eggs. The discoloration of infected tissue may haved/or oxidation of phenolic compounds as suggested for certain root-knot nematodes.

METHOD: Reproductive Efficiency CONDITIONS: Green House and Field METHOD NARR: Tests of tuber resistance and reproductive efficiency to M. chitwoodi races 1 & 2, and M. hapla, were performed in microplots of 19L volume buckets pa. These micro plots were inoculated with 25,000 eggs and allowed to grow for 90-135 days until harvest. Egg counts were made and tuber damage was rated. Additionally, tests for reproductive efficiency were carried out in tTION: Analysis of the hybrids makes it appear that resistance to race 1 is inherited in a discrete fashion. Resistance appears to be a dominant character.

METHOD: Visual Examination ; Body Count CONDITIONS: Field METHOD NARR: The mean number of aphids (GPAPHID and PAPHID) per plant was calculated for 1 or more trials per accession. Species with a mean insect score less than the ovtandard deviation were considered resistant, and species with a mean score higher than the overall mean score plus one standard deviation were considered susceptible.

Myzus persicae and Ma. euphorbiae were reared on S. tuberosum cv. Desiree plants in environmental chambers. For each aphid species, at least 50 nymphs younger than 24 h were transferred in microcages clipped on the lower face of a potato leaf at the third or fourth level from the apex (10 plants with five nymphs per microcage). For each aphid species, two groups of five plants from the same accession or the standard were randomly placed in environmental chambers. Emerged adult aphids were each isolated in a microcage, and their demographic parameters were evaluated every third day during a period equivalent to their prereproductive period (Le Roux et al., 2004). Nymph survival, prereproductive period, that is the period of time from birth until onset of reproduction, adult survival and calculated daily fecundity were assessed for each accession. For each feeding assay, the intrinsic rate of natural increase was calculated.

Study Name: Resistance to leaf hopper, flea beetle, peach aphid, tarnish Experiment Type: Field FIELD Study Year: 1985 Year started: 04/01/1986 Year ended: 05/01/1987. Seeds were germinated and a plot of six plants were transplanted in the field in 12 row blocks. Each block was bordered by an eight meter strip of alfalfa which was planted to attract and retain the pests. Bug samples were taken four times during the summer growing period by the use of vacuum sampling. These samples were frozen and evaluated during the winter months by identifying and tallying each pest in the sample. A total count was determined from the four samples for potato leaf hopper adults and nymphs (P1, P2), tarnish beetle adults and nymphs (P3, P4), potato aphid adults (P5), and potato flea beetle adults (P6). The natural log of the total count was then found.

Overlaid on these materials were investigations to determine the effects due to environment in which the tubers were produced, and tuber maturity differences resulting from longer storage. The default environment for tuber generation was randomized units in 6 inch clay pots in potting medium in either the winter greenhouse or summer screenhouse at USPG, with storage of 1 month or less at 5 degrees such that tubers were firm with no sprouting. The effects of various methods of sample preparation were also assessed. The default sampling technique was to place representative samples of washed whole tubers in self-sealing plastic bags, freeze at -20 degrees, thaw to room temperature, crush to express and homogenize juice, and measure pH in the bag with a "Hanna Instruments pH 210" processing meter using a Corning #476346 probe calibrated with 4.0 and 7.0 standard buffers. Unless otherwise noted below, these default tuber generation and preparation standards apply. Standard ANOVA and Pearson's correlation was used to assess the statistical significance of mean separations, and size and significance of paired observations, respectively.

Tubers were produced in three reps: 1) tuberlings grown in Kula, Maui, HI field; 2) seedlings grown in Kula, Maui, HI field; and 3) seedlings grown in greenhouse in Strugeon Bay, WI. Total phenolic content was determined following the method of Singleton et al. (1999). Chlorogenic acid was used as a standard, and PHEN expressed as micrograms of chlorogenic acid equivalents per gram of tuber fresh weight. An average was calculated from the three tuber reps.

Ploidy determination by counting the chloroplasts contained in stomata guard cells or examining the size of the guard cells is not an exact technique for the determination of ploidy of a genotype, but does allows for the distinction of the diploid group from the other groups. Begin by collecting leaflets from the upper third of genotype to be evaluated. Place 1 or 2 drops of Iodine‐potassium iodide solution (I‐KI) in the center of a slide. With the help of fine‐point tweezers, remove the epidermal tissue from the underside of the leaf, from an area close to the veins, and immediately place it gently on the slide. Add another drop of the Iodine‐potassium iodide solution and cover with a coverslip. Examine under an optical microscope at a magnification of 100, 200 or 400X. Ploidy can be determined by looking at the size of the guard cell (L. Kramer and J. Bamberg, 2018) or via chloroplast count (Technical Manual - Potato reproductive and cytological biology - Benny Ordoñez, Matilde Orrillo and Merideth Bonierbale - 2017 International Potato Center).

Study Name: Resistance to Potato Leaf Roll Virus Experiment Type: Field FIELD Study Year: 1983 Year started: 05/17/1983 Year ended: 12/14/1983 Comment: Six plants of each accession were tested. They were trans- planted in the field after being infested with PLRV infected green peach aphids. Visual evaluations of PLRV symptoms and ELISA tests were later done on leaf collections.

Study Name: Resistance to Potato Leaf Roll Virus Experiment Type: Field FIELD Study Year: 1984 Year started: //1984 Year ended: 12/12/1984. Infected green peach aphids were scattered over seedlings grown in the greenhouse. Plants were transplanted to the field where visual observation and two ELISA assays about a week apart were made. A third ELISA test was made on the most resistant entries.

Study Name: Resistance to Potato Leaf Roll Virus Experiment Type: Greenhouse GREENHOUSE Study Year: 1983 Year started: 04/01/1983 Year ended: 10/26/1983. Seedlings were screened in the greenhouse by exposing plants from each accession to two PLRV infected green peach aphids for 48 hours. Plants were scored on visual symptoms.

Study Name: Resistance to Potato Leaf Roll Virus Experiment Type: Greenhouse GREENHOUSE Study Year: 1984 Year started: 11/11/1983 Year ended: 12/14/1984. Seedlings were planted in the greenhouse and then inoculated with PLRV by exposing every second plant in the flat with two PLRV infected green peach aphids for 48 hours. Plants were visually assessed for PLRV symptoms and given a rating (1-4).

METHOD: ELISA, grafting METHOD NARR: Resistance to PLRV by chc was tested by aphid inoculation and two forms of graft testing (i.e., as a healthy scion grafted on infected D. tatula and as a healthy stock receiving an infected potion). Virus could not be detected directly by ELISA, but infection was verified by graft backtests to D. tatula. RESULTS NARR: A high level of resistance to PLRV in chc 133124 was observed. AUTHOR EXPLANATION: It is noity to the virus exists, because of the ambiguity of the definition of immunity. Resistance was shown to be to the virus rather than to the vector by use of graft inoculations.

METHOD: ELISA METHOD NARR: Five viruliferous aphids were confined on each plant for 5-6 days. Plants were assayed at 4-5 weeks and 8-9 weeks for PLRV using ELISA (PLRV test kit, Agdia, Inc.). Background ELISA readings are 0.01-0Tbr was susceptible while Brd was resistant. Somatic hybrids between these two parents were largely resistant as well.

Study Name: Resistance to Potato Leaf Roll Virus Experiment Type: Field FIELD Study Year: 1984 Year started: 05/01/1984 Year ended: 02/14/1985. Each plant was inoculated with five infected green peach aphids. Plants with visual symptoms were labeled susceptible, and plants which showed no visual symptoms were given two ELISA tests. One ELISA test was made on the plants in the field, the other plants were tested after being re-rooted in the greenhouse.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House METHOD NARR: Four viruses, 1 fungus and 1 nematode were used to test for resistance. Tubers were used except for non-tuber-bearing accessions. Viruses PVA,PVM anmechanically using carborundum, and PLRV was transmitted by apterous aphids. Symptoms were monitored visually and ELISA's were performed. Accessions identified as resistant were retested to confirm resistance. RESULTS NARRaccessions carried one or more resistances. AUTHOR EXPLANATION: All tubers obtained from one accession were bulked due to limited tuber production under given conditions. Therefore, the results can not be generalized to theof resistance are discussed. It is noted when the results obtained in this study do not match those of previous studies and explanations are offered.

Study Name: Resistance to Potato Leaf Roll Virus Experiment Type: Screenhouse SCREENHOUSE Study Year: 1984 Year started: 04/01/1984 Year ended: 11/19/1984 Comment: After the seeds were germinated, 18 plants were trans- planted. Fifteen of the 18 plants were inoculated with 300 viruliferous aphids, the other three were kept as controls. All plants with no visual symptoms were ELISA essayed.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

Study Name: Pollen shed. Experiment Type: Field FIELD Study Year: 1992 Year started: 05/06/1992 Year ended: 09/23/1992

Study Name: Pollen stainability. Experiment Type: Field FIELD Study Year: 1992 Year started: 05/06/1992 Year ended: 09/23/1992

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: Feeding Behavior CONDITIONS: Green House and Field - 16h light at 24C METHOD NARR: Laboratory antibiosis tests counted and weighed mature pupae and the time it took to reach the pupal stage, after infesting tubers with laenosis tests counted leaf mines and tuber mines, and overall weight of tubers per plant at harvest. RESULTS NARR: The highest antibiosis effect expressed as total larval mortality on tubers was found in all pnt and 2 spl ceffect of tubers was observed in some spl genotypes. The wild species tested in the field antixenosis test had a low level of infestation throughout the life cycle of the plant, with little dependence on phenological factors.wide range of larval survival observed among clones derived from 2 spl PIs indicates a segregation for resistance. A polygenic or oligogenic control of the antibiosis is hypothesized. The exudate of type B trichomes had a strong antid ovipositioning females and work by other authors is mentioned regarding this influence.

METHOD: Life Cycle CONDITIONS: Green House - 16h light at 26C METHOD NARR: Excised leaves were used in both Host Choice Assays and No-Choice Assays. In both cases, the number of eggs laid on foliage and the surface of the cage wtched unfed larvae were placed individually on excised leaves and their behavior was observed for standard feeding and grooming activities, agitation and movement. Larval Mortality, Developmental Period, Leaf Consumption andined. RESULTS NARR: Performance of potato tuberworm on foliage of ber was negatively affected compared with performance on foliage of cultivated potato. AUTHOR EXPLANATION: The most significant differences were observed intypes (A & B) of trichomes.

METHOD: Oviposition CONDITIONS: Green House - 16h light at 26C METHOD NARR: Leaves of ber 473331 and 473334 were appressed to tbr cv. Altantic leaflets and presented to PTM adults. Eggs laid on both surfaces of the leaflets werell varieties were subjectd to 4 different treatments designed to remove trichomes and/or their exudates. Again, eggs on leaves were counted as well as those deposited on the cage. Leaf area consumption was determined by traviors were recorded. Trichome density was measured. Sugar ester content of type B trichomes of 473331 was determined. RESULTS NARR: Appressing ber 473331 foliage against a susceptible cultivar dramatically reduced acceptancn. Aggressive removal of the trichomes led to even greater ovipositional acceptance. Neonates on ber 331 required more time to penetrate the leaf surface. Results suggest that the glandular trichomes of ber 331 limit post-penetratio larvae. AUTHOR EXPLANATION: PTM females prefer hirsute surfaces for egg laying, but this tendancy is masked by the presence of hirsute-like trichomes. Trichomes produce a variety of negative behavioral and developmentosition deterrence as the most significant factor.

METHOD: Oviposition CONDITIONS: Green House - 16h light with 70% RH and 24C METHOD NARR: An antibiosis test was carried out by recording # of pupae and their weight after confining first instar larvae on detached leaves of each pition preference was determined by a 2 X 2 comparison including a control cultivar, and a 4 X 4 comparison only some of which contained the control cultivar. A feeding preference assay was also completed using those accessioting and characterization of trichomes was performed using samples found in the previous tests. RESULTS NARR: A lack of association between trichome A density and antixenosis was demonstrated. No correlations between larvalwas found. All tested clones of pnt exerted some antibiotic effect on the larvae. The pnt clone tested foor antixenosis proved to repel the ovipositing female. Ber genotypes with a high rate of type b trichomes repulsed oviposition.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 18-22C with light intensity of 3-5Klux METHOD NARR: A large number of accessions were tested by mechanical inoculation with PVY n,o,and c. These preliminary rescreening of accessions that appeared to be resistant to the virus including top-graft inoculation via infected Nicotiana. In all cases virus titre was verified by ELISA and in some cases by tobacco-bioassay and dot-immunobined as diagnostic hosts were tested for susceptibility to PVA, PVM, PVS, and PVX. RESULTS NARR: Two accessions of sto were found to be immune to PVYn. Chc 472819 can be used to identify PVYn and PVYo strains. AUTHOR EXPLANATions useful as indicator plants and the particular symptoms they differed by, were presented.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 14h light, 18-22C or 20-29C with light intesity of4-8 Klux METHOD NARR: Mcd were tested for susceptibility and symptom expression to various viruses with PVA beiest. The plants were mechanically inoculated and infection was confirmed using ELISA. AUTHOR EXPLANATION: Mcd is a suitable diagnostic host for PVA.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: ELISA, ISEM and Visual Examination CONDITIONS: Green House - 18h light with light intensity 150umol. Daily minimum temp 19C, maximum temp 24C. METHOD NARR: In vitro plantlets were transplanted to soil. The viruses wereplants of each clone, in each of the 2 or 3 experiments carried out for each strain, both mechanically and by graft. ELISA and ISEM were used for detection 21 and 28 days after mechanical and graft inoculation respectively.ed for PVA. AUTHOR EXPLANATION: Differences in response to inoculation by mechanical means versus grafting are noted. Temperature can affect the development of necrosis with HR rendered less effective at higher temps. Remarstance phenotyoes were determined.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House METHOD NARR: Four viruses, 1 fungus and 1 nematode were used to test for resistance. Tubers were used except for non-tuber-bearing accessions. Viruses PVA,PVM anmechanically using carborundum, and PLRV was transmitted by apterous aphids. Symptoms were monitored visually and ELISA's were performed. Accessions identified as resistant were retested to confirm resistance. RESULTS NARRaccessions carried one or more resistances. AUTHOR EXPLANATION: All tubers obtained from one accession were bulked due to limited tuber production under given conditions. Therefore, the results can not be generalized to theof resistance are discussed. It is noted when the results obtained in this study do not match those of previous studies and explanations are offered.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 18-22C with light intensity of 3-5Klux METHOD NARR: A large number of accessions were tested by mechanical inoculation with PVY n,o,and c. These preliminary rescreening of accessions that appeared to be resistant to the virus including top-graft inoculation via infected Nicotiana. In all cases virus titre was verified by ELISA and in some cases by tobacco-bioassay and dot-immunobined as diagnostic hosts were tested for susceptibility to PVA, PVM, PVS, and PVX. RESULTS NARR: Two accessions of sto were found to be immune to PVYn. Chc 472819 can be used to identify PVYn and PVYo strains. AUTHOR EXPLANATions useful as indicator plants and the particular symptoms they differed by, were presented.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: Both and Visual Examination CONDITIONS: Green House METHOD NARR: Collections made by D. Spooner and A. Contreras in region X of Chile in 1989 were maintained as root stocks and grown in a GH. Leaflets were collected andion of PVS, PVM, PVX, AMV, PYV and APLV. A survey of frn on Robinson Crusoe Island was done and insects infesting the plants were noted as possible virus transmission vectors. RESULTS NARR: A total of 47 clones of the Chion were tested. AMV and APLV were not found. Infection was detected as follows: PVS - 89%, PVM - 43%, PVX - 38% and PYV - 15%. On RC Island, plants were infested by Myzus persicae and Aulacorthum solani. PVS, PVM and PVX wer PYV were not. AUTHOR EXPLANATION: PVY is reported here for the first time as occuring outside of Peru.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House METHOD NARR: Four viruses, 1 fungus and 1 nematode were used to test for resistance. Tubers were used except for non-tuber-bearing accessions. Viruses PVA,PVM anmechanically using carborundum, and PLRV was transmitted by apterous aphids. Symptoms were monitored visually and ELISA's were performed. Accessions identified as resistant were retested to confirm resistance. RESULTS NARRaccessions carried one or more resistances. AUTHOR EXPLANATION: All tubers obtained from one accession were bulked due to limited tuber production under given conditions. Therefore, the results can not be generalized to theof resistance are discussed. It is noted when the results obtained in this study do not match those of previous studies and explanations are offered.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 18-22C with light intensity of 3-5Klux METHOD NARR: A large number of accessions were tested by mechanical inoculation with PVY n,o,and c. These preliminary rescreening of accessions that appeared to be resistant to the virus including top-graft inoculation via infected Nicotiana. In all cases virus titre was verified by ELISA and in some cases by tobacco-bioassay and dot-immunobined as diagnostic hosts were tested for susceptibility to PVA, PVM, PVS, and PVX. RESULTS NARR: Two accessions of sto were found to be immune to PVYn. Chc 472819 can be used to identify PVYn and PVYo strains. AUTHOR EXPLANATions useful as indicator plants and the particular symptoms they differed by, were presented.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: Both and Visual Examination CONDITIONS: Green House METHOD NARR: Collections made by D. Spooner and A. Contreras in region X of Chile in 1989 were maintained as root stocks and grown in a GH. Leaflets were collected andion of PVS, PVM, PVX, AMV, PYV and APLV. A survey of frn on Robinson Crusoe Island was done and insects infesting the plants were noted as possible virus transmission vectors. RESULTS NARR: A total of 47 clones of the Chion were tested. AMV and APLV were not found. Infection was detected as follows: PVS - 89%, PVM - 43%, PVX - 38% and PYV - 15%. On RC Island, plants were infested by Myzus persicae and Aulacorthum solani. PVS, PVM and PVX wer PYV were not. AUTHOR EXPLANATION: PVY is reported here for the first time as occuring outside of Peru.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: ELISA, ISEM and Visual Examination CONDITIONS: Green House - 18h light with light intensity 150umol. Daily minimum temp 19C, maximum temp 24C. METHOD NARR: In vitro plantlets were transplanted to soil. The viruses wereplants of each clone, in each of the 2 or 3 experiments carried out for each strain, both mechanically and by graft. ELISA and ISEM were used for detection 21 and 28 days after mechanical and graft inoculation respectively.ed for PVA. AUTHOR EXPLANATION: Differences in response to inoculation by mechanical means versus grafting are noted. Temperature can affect the development of necrosis with HR rendered less effective at higher temps. Remarstance phenotyoes were determined.

Both ELISA and Visual Examination METHOD NARR: Wild Solanum species were inoculated by carborundum-spatula technique with diluted sap from Nicotiana previously infected with PVX and PVY. Visual inspections every 7 days and ELISA at the end of 3rd and 6th weeks. In latent host-virus relations back-inoculation to indicator plants was carried out. Visual observations include specific sets of symptoms. Specific ELISA scores not noted. AUTHOR EXPLANATION: Addresses local vs. systemic susceptibility and hypersensitive response.

Resistance to viruses was carried by methods of mechanical infection by 3 PVY stamms and 1 PVX stamm. The plants were divided in 3 groups of resistance: R-resistant, MR-medium resistant and S-susceptible.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 18-22C with light intensity of 3-5Klux METHOD NARR: A large number of accessions were tested by mechanical inoculation with PVY n,o,and c. These preliminary rescreening of accessions that appeared to be resistant to the virus including top-graft inoculation via infected Nicotiana. In all cases virus titre was verified by ELISA and in some cases by tobacco-bioassay and dot-immunobined as diagnostic hosts were tested for susceptibility to PVA, PVM, PVS, and PVX. RESULTS NARR: Two accessions of sto were found to be immune to PVYn. Chc 472819 can be used to identify PVYn and PVYo strains. AUTHOR EXPLANATions useful as indicator plants and the particular symptoms they differed by, were presented.

METHOD: ELISA, Visual Examination, slot-blot hybridization CONDITIONS: In Vitro - 16h light at 22C with light intensity of 6Klux METHOD NARR: Solanum species were mechanically innoculated with PVXcp. Estimates of PVX multiplicaELISA and slot-blot hybridization. Graft inoculation tests were used to confirm cases of extreme resistance. Results are given as mg PVX/g concentrations (range: 0.8-40) and visual symptoms. Hybridization results confirmedNATION: To asses PVX levels, an internal calibration curve was constructed by sampling a range of 4-600ng of purified PVX per well in each ELISA plate. Relative PVX concentration levels in 5 genotypes graft-inoculated are expe PVX concentration level in the tested genotype and its susceptible partner.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: Both and Visual Examination CONDITIONS: Green House METHOD NARR: Collections made by D. Spooner and A. Contreras in region X of Chile in 1989 were maintained as root stocks and grown in a GH. Leaflets were collected andion of PVS, PVM, PVX, AMV, PYV and APLV. A survey of frn on Robinson Crusoe Island was done and insects infesting the plants were noted as possible virus transmission vectors. RESULTS NARR: A total of 47 clones of the Chion were tested. AMV and APLV were not found. Infection was detected as follows: PVS - 89%, PVM - 43%, PVX - 38% and PYV - 15%. On RC Island, plants were infested by Myzus persicae and Aulacorthum solani. PVS, PVM and PVX wer PYV were not. AUTHOR EXPLANATION: PVY is reported here for the first time as occuring outside of Peru.

METHOD: Both ELISA and Visual Examination METHOD NARR: Seven plants of 15 accessions each of sto and dms were mechanically inoculated with PVYntn. Plants were symptomatologically checked every 7 days and ELISA performed after 5 worbance of the 7 replicates was recorded. ELISA was considered positive if absorbance values exceeded twice that of the healthy control samples. Back-inoculation was also used. RESULTS NARR: Ten of the 15 sto accessions immune. Of the 15 dms accessions none were found to be resistant. AUTHOR EXPLANATION: Sources of resistance are discussed.

METHOD: Both ELISA and Visual Examination METHOD NARR: Sto accessions were inoculated with PVY and HeMV. There were visual inspections every 7 days with ELISA at the end of weeks 3 and 6. No ELISA data is provided, only susceptimless plants were back-inoculated on indicator plants. RESULTS NARR: Eight of the sto accessions were found to be immune to PVY and 6 to HeMV. Three were immune t both viruses.

Leaves of each plant were mechanically inoculated at six points with a Paasche model H airbrush (Chicago) at 40 psi using carborundum power as an abrasive. The inoculum was made by extracting sap from leaves of infected tobacco plants (3 g of leaf per 100 ml of 0.1 M potassium phosphate buffer, pH 7.0). Plants were inoculated at the seven to eight-leaf stage (4 to 6 weeks after transplanting). Four weeks after inoculation, plants were visually evaluated for virus symptoms (leaf chlorosis, lower leaf necrosis, and leaf drop). Uninoculated leaves from asymptomatic plants were tested for the presence of PVY using a doubleantibody sandwich enzyme-linked immunosorbent assay (ELISA). Absorption at 405 nm was measured with an ELISA reader (Bio-TEK, ELx800). Absorbance values of uninoculated control samples were 0.00 to 0.01. PVY is not transmitted through true potato seed; therefore, all uninoculated seedlings were virus-free. ELISA absorbance values were 0.0 to 3.0. Plants were considered resistant if they exhibited scores <0.1 in the initial screen and after reinoculation. Plants were considered susceptible if they exhibited symptoms or if any leaf samples had ELISA scores ?0.1. Data from the ELISA tests were censored because 3.0 was the maximum ELISA absorbance value recorded. Because of this scoring system, a binary data set was analyzed. Plants with absorbance values consistently <0.1 were given a value of 0 (resistant) and all others were given a value of 1 (susceptible).

Resistance to viruses was carried by methods of mechanical infection by 3 PVY stamms and 1 PVX stamm. The plants were divided in 3 groups of resistance: R-resistant, MR-medium resistant, and S-susceptible.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House METHOD NARR: Four viruses, 1 fungus and 1 nematode were used to test for resistance. Tubers were used except for non-tuber-bearing accessions. Viruses PVA,PVM anmechanically using carborundum, and PLRV was transmitted by apterous aphids. Symptoms were monitored visually and ELISA's were performed. Accessions identified as resistant were retested to confirm resistance. RESULTS NARRaccessions carried one or more resistances. AUTHOR EXPLANATION: All tubers obtained from one accession were bulked due to limited tuber production under given conditions. Therefore, the results can not be generalized to theof resistance are discussed. It is noted when the results obtained in this study do not match those of previous studies and explanations are offered.

METHOD: Both ELISA and Visual Examination CONDITIONS: Green House - 18-22C with light intensity of 3-5Klux METHOD NARR: A large number of accessions were tested by mechanical inoculation with PVY n,o,and c. These preliminary rescreening of accessions that appeared to be resistant to the virus including top-graft inoculation via infected Nicotiana. In all cases virus titre was verified by ELISA and in some cases by tobacco-bioassay and dot-immunobined as diagnostic hosts were tested for susceptibility to PVA, PVM, PVS, and PVX. RESULTS NARR: Two accessions of sto were found to be immune to PVYn. Chc 472819 can be used to identify PVYn and PVYo strains. AUTHOR EXPLANATions useful as indicator plants and the particular symptoms they differed by, were presented.

METHOD: Both ELISA and Visual Examination METHOD NARR: Seven plants of each accession were mechanically inoculated with PVYntn at the 8-10 leaf stage. Plants were checked visually for symptoms and ELISA was performed 5 weeks afte

METHOD: Both and Visual Examination METHOD NARR: Accessions were mechanically inoculated with PVYntn and TMV. The plants were symptomatologically checked and ELISAs were performed.Back inoculations were carried out using Nicotiar plants. RESULTS NARR: Only one accession was immune to PVYntn infection - PI584492. None of the accessions showed local hypersensitive reactions.

METHOD: ELISA CONDITIONS: Green House - 16h light with mean day/night temp. 26C/16C and light intensity of 14-22Klux METHOD NARR: Etuberosa group frn was graft-inoculated with many viruses. The plants were tested using ELISA, NAting to a susceptible control. Uninoculated plants were also tested to provide background readings. ELISA absorbances are given. RESULTS NARR: Back-grafting to a susceptible control sometimes resuted in positive ELISA reested indicating transfer of the virus from a resistant accession.

METHOD: Both and Visual Examination CONDITIONS: Green House METHOD NARR: Collections made by D. Spooner and A. Contreras in region X of Chile in 1989 were maintained as root stocks and grown in a GH. Leaflets were collected andion of PVS, PVM, PVX, AMV, PYV and APLV. A survey of frn on Robinson Crusoe Island was done and insects infesting the plants were noted as possible virus transmission vectors. RESULTS NARR: A total of 47 clones of the Chion were tested. AMV and APLV were not found. Infection was detected as follows: PVS - 89%, PVM - 43%, PVX - 38% and PYV - 15%. On RC Island, plants were infested by Myzus persicae and Aulacorthum solani. PVS, PVM and PVX wer PYV were not. AUTHOR EXPLANATION: PVY is reported here for the first time as occuring outside of Peru.

METHOD: ELISA, ISEM and Visual Examination CONDITIONS: Green House - 18h light with light intensity 150umol. Daily minimum temp 19C, maximum temp 24C. METHOD NARR: In vitro plantlets were transplanted to soil. The viruses wereplants of each clone, in each of the 2 or 3 experiments carried out for each strain, both mechanically and by graft. ELISA and ISEM were used for detection 21 and 28 days after mechanical and graft inoculation respectively.ed for PVA. AUTHOR EXPLANATION: Differences in response to inoculation by mechanical means versus grafting are noted. Temperature can affect the development of necrosis with HR rendered less effective at higher temps. Remarstance phenotyoes were determined.

Study Name: Resistance to Rhizoctonia Solani. Experiment Type: Greenhouse GREENHOUSE Study Year: 1989 Year started: 05/01/1989 Year ended: 01/23/1990 Comment: Three replications of each accession were planted and inocul ated or not inoculated with R. solani. A rhizoctonia rating (0-4) was given to each accession.

METHOD: Both IFAS and Visual Examination CONDITIONS: Green House - minimum of 12h light. Temperature ranged from 20-32C. METHOD NARR: Tissue-cultured plantlets were air dried 20 minutes then their roots were immersed in 10ml ofor 20 minutes. They were then planted in soil and monitored for ring rot for 72 days. IFAS was used to detect bacterial cells in stem sections. RFLP and RAPD analyses were also performed. RESULTS NARR: Two accessions weterial ring rot. The results identify parents suitable for future mapping of genes for immunity or resistance. AUTHOR EXPLANATION: The number of cells per well was recorded as the average # of cells viewed in 10 fields. IFA1=0-10 cells/field, 2=11-20 cells/field, 3=21-50 cells/field, 4=>50 cells/field. Bacterial ring rot reactions were based on a combination of IFAS and incidence of symptomatic plants: Susceptible= >15% symptomatic plants and IFAS of 1-symptomatic plants and IFAS of 1-4. Highly Resistant= 0% symptomatic plants and IFAS of 0.1-0.9. Immune= 0% symptomatic plants and IFAS of 0.

METHOD: Both IFAS and Visual Examination CONDITIONS: Green House - 18h light METHOD NARR: Roots and basal stems of 4-wk old plants were inoculated with Clavibacter michiganensis subsp. sepedonicus strain NDCs-OFF by placing themurs. Symptoms were noted 6 weeks post-inoculation. Stem tissue samples were prepared for IFAS to determine C.m. subsp. sepedonicus populations. In a second screening, analysis was based only on IFAS testing due to atypicalt screening. Stability of immune clones was tested by repeating the test with rooted cuttings. Test clones of acl with potential immunity were further analysed using cuttings and also tuber grown clones. RESULTS NARR: Trialings): 0 IFU/MF=Immune, 1-10 IFU/MF=Resistant, 11-20 IFU/MF=Low Resistance, >20 IFU/MF=Susceptible. Immune Test Clone Trials: 0 IFU/g=Immune, 10-100 IFU/g=Resistant, 1000-10000 IFU/g=Low Resistance, >100000 IFU/g=Susceptible. AUTHORth conditions such as light sensitivity and intensity may have affected the results. Apparent immunity in some species may have resulted from improper inoculation or a form of young seedling resistance. There are many acof resistance among clones and between screenings, making a resistance rating difficult.

METHOD: Both IFAS and Visual Examination CONDITIONS: Green House - 12h light METHOD NARR: One month after planting TPS, roots were washed clean and immersed in a suspension of C. sepedonicum for five minutes. Those plants that wfour weeks were stem inoculated with 100ul of cell suspension. Some accessions were also tuber inoculated. A thin slice was removed from the stem end of each tuber. Tubers were then soaked in bacterial suspension for fivere not made on symptomless plants. Plants were evaluated for up to 12 weeks. Following the final assessment, symptomless plants were IFAS tested. RESULTS NARR: IFAS results as based on a mean of 10 fields: 0 = No Cells, +/- 2+ = 11-20 cells, 3+ = 21-50 cells, 4+ = >50 cells. AUTHOR EXPLANATION: The differences between the two inoculation methods (tuber vs root) may account for the difference in apparent symptomless rates. The results in this study diies and this may be cause by differences in day length or total light energy.

A vigorous root system could be related to traits desired in the potato crop such as efficient water and fertilizer use. Because wild species are adapted to a broad range of soil environments, they may contain useful variation not available in the cultivar breeding pool. Roots are very difficult to measure, especially in field conditions. We grew 75 accessions (3 accessions of each of 25 species) in Perlite as seedling replicates in clay pots in a summer screenhouse. They were harvested at the same time, all being at about the same physiological maturity (just reaching full flowering). Roots were separated from the rest of the plant (top). The tissue was air, then oven dried and weighed. These results appear to have a relationship with those of Errebhi et al. who measured nitrogen uptake efficiency. S. chacoense and S. microdontum had the highest total biomass production in N-deficient growing conditions and the greatest N uptake efficiency. In our study, S. chacoense had by far the most root production and microdontum ranked 7th of 25. Errebhi et al. found a large difference between the two accessions of kurtzianum they tested for the two parameters mentioned above. Our results with these same accessions found the poor N user produced only 60% as much roots as the efficient N user. More work and analysis needs to be done in this area. However, preliminary indications suggest that screening for root dry weight of pot-grown plants might have usefulness as a relatively simple way to predict field performance of germplasm with respect to use of soil resources. Reference: Errebhi et al. 1998. Screening of exotic potato germplasm for nitrogen uptake and biomass production. AJPR 75:93-100.

This data is from a Master’s Thesis of Gulden Zont, 1997, Dept Soil Science, University of Wisconsin, Madison, major professor P. K. Barak. Twenty-four aeroponic chambers of a type described by Peterson and Krueger (1988) and used by Barak et al., (1996) were prepared (Figure 2. 1). Each chamber lid held four seedling plants with support of plugs inserted into a Styrofoam cover with a drain at the bottom of the root chamber. Supplies of nutrient solutions for three chambers were stored in 17-liter stainless-steel canisters and dispensed through spray nozzles using timer-activated solenoids. Nutrient solution was intermittently misted on the roots at a rate of approximately 5 ml, at an interval of every 5 minutes. Supplemental light was provided with high-pressure sodium halide lights to ensure 16 h of light per day. Two experiments were done in January and June, 1997, each lasting about 55 days. The plants from each container were combined and separated into roots, shoots and tubers and fresh weights were measured. Samples were dried in a forced-air oven at 65°C for 7 days and parts weighed. Results of the two experiments were pooled and summarized by USPG staff for the data presented in GRIN. Barak, P., Smith, J.D., Krueger, A.R., and Peterson, L.A. 1996. Measurement of short-term nutrient uptake rates in cranberry by aeroponics. Plant, Cell, Environ. 19:237-242. Peterson, L.A., Krueger, A.R. 1988. An intermittent aeroponics system. Crop Science, 28:7 12-7 13.

Salinity Screening - 20mM solution. CONDITIONS: Green House - 18-25C METHOD NARR: Salt treatments consisted of water solutions containing 0, 40, 80, and 120mM NaCl and 20 and 40 mM Na2SO4. The treatments were increased in gradual increments of 20mM per day to prevent severe stress. RESULTS NARR: Sodium sulfate reduced plant survival more than sodium chloride on an equal molar basis. AUTHOR EXPLANATION: SO4 ions were more toxic than Cl ions. Survival of an accession treated with one salt was a good indicator of survival with the second. There was no relationship between accessions of known heat or drought resistance and salt resistance.

Salinity Screening - 40mM solution. CONDITIONS: Green House - 18-25C METHOD NARR: Salt treatments consisted of water solutions containing 0, 40, 80, and 120mM NaCl and 20 and 40 mM Na2SO4. The treatments were increased in gradual increments of 20mM per day to prevent severe stress. RESULTS NARR: Sodium sulfate reduced plant survival more than sodium chloride on an equal molar basis. AUTHOR EXPLANATION: SO4 ions were more toxic than Cl ions. Survival of an accession treated with one salt was a good indicator of survival with the second. There was no relationship between accessions of known heat or drought resistance and salt resistance.

Salinity Screening - 40mM solution. CONDITIONS: Growth Chamber - 16h light at 25C METHOD NARR: Plantlets were grown in media containing various salinity levels. The single-node cutting bioassay produced data on root lengths and fresh & dry weights at each salinity level. The root tip segment bioassay produced data on root extension growth relative to growth in control medium, for both solid and liquid medium. The microtuberization bioassay produced data on microtuber yield and size distribution per container. The lysimeter experiment measured tuber yield and grade per plant. RESULTS NARR: Plantlet growth parameters were not affected by 40mM NaCl, while 80 and 120 mM NaCl significantly reduced all plantlet growth parameters compared with control and each other in the single-node cutting assay. In the root tip segment assay, the impact on root growth was less in liquid than in solid medium in 40 & 80mM NaCl, but similar in the 120mM treatment. All genotypes were inhibited at 40mM/solid except PI473403. AUTHOR EXPLANATION: It appears that salinity tolerance can be credibly evaluated in vitro. Low to mid-range salinity levels cannot be used to predict genotype tolerance at higher levels. None of the 6 growth parameters used in the single-node cutting assay was a better indicator of salinity ranking than any of the others. The single node cutting assay is recommended as the best in vitro screen.

Salinity Screening - 80mM solution. CONDITIONS: Green House - 18-25C METHOD NARR: Salt treatments consisted of water solutions containing 0, 40, 80, and 120mM NaCl and 20 and 40 mM Na2SO4. The treatments were increased in gradual increments of 20mM per day to prevent severe stress. RESULTS NARR: Sodium sulfate reduced plant survival more than sodium chloride on an equal molar basis. AUTHOR EXPLANATION: SO4 ions were more toxic than Cl ions. Survival of an accession treated with one salt was a good indicator of survival with the second. There was no relationship between accessions of known heat or drought resistance and salt resistance.

Salinity Screening - 80mM solution. CONDITIONS: Growth Chamber - 16h light at 25C METHOD NARR: Plantlets were grown in media containing various salinity levels. The single-node cutting bioassay produced data on root lengths and fresh & dry weights at each salinity level. The root tip segment bioassay produced data on root extension growth relative to growth in control medium, for both solid and liquid medium. The microtuberization bioassay produced data on microtuber yield and size distribution per container. The lysimeter experiment measured tuber yield and grade per plant. RESULTS NARR: Plantlet growth parameters were not affected by 40mM NaCl, while 80 and 120 mM NaCl significantly reduced all plantlet growth parameters compared with control and each other in the single-node cutting assay. In the root tip segment assay, the impact on root growth was less in liquid than in solid medium in 40 & 80mM NaCl, but similar in the 120mM treatment. All genotypes were inhibited at 40mM/solid except PI473403. AUTHOR EXPLANATION: It appears that salinity tolerance can be credibly evaluated in vitro. Low to mid-range salinity levels cannot be used to predict genotype tolerance at higher levels. None of the 6 growth parameters used in the single-node cutting assay was a better indicator of salinity ranking than any of the others. The single node cutting assay is recommended as the best in vitro screen.

Salinity Screening - 120mM solution. CONDITIONS: Green House - 18-25C METHOD NARR: Salt treatments consisted of water solutions containing 0, 40, 80, and 120mM NaCl and 20 and 40 mM Na2SO4. The treatments were increased in gradual increments of 20mM per day to prevent severe stress. RESULTS NARR: Sodium sulfate reduced plant survival more than sodium chloride on an equal molar basis. AUTHOR EXPLANATION: SO4 ions were more toxic than Cl ions. Survival of an accession treated with one salt was a good indicator of survival with the second. There was no relationship between accessions of known heat or drought resistance and salt resistance.

Salinity Screening - 120mM solution. CONDITIONS: Growth Chamber - 16h light at 25C METHOD NARR: Plantlets were grown in media containing various salinity levels. The single-node cutting bioassay produced data on root lengths and fresh & dry weights at each salinity level. The root tip segment bioassay produced data on root extension growth relative to growth in control medium, for both solid and liquid medium. The microtuberization bioassay produced data on microtuber yield and size distribution per container. The lysimeter experiment measured tuber yield and grade per plant. RESULTS NARR: Plantlet growth parameters were not affected by 40mM NaCl, while 80 and 120 mM NaCl significantly reduced all plantlet growth parameters compared with control and each other in the single-node cutting assay. In the root tip segment assay, the impact on root growth was less in liquid than in solid medium in 40 & 80mM NaCl, but similar in the 120mM treatment. All genotypes were inhibited at 40mM/solid except PI473403. AUTHOR EXPLANATION: It appears that salinity tolerance can be credibly evaluated in vitro. Low to mid-range salinity levels cannot be used to predict genotype tolerance at higher levels. None of the 6 growth parameters used in the single-node cutting assay was a better indicator of salinity ranking than any of the others. The single node cutting assay is recommended as the best in vitro screen.

METHOD: Visual Examination CONDITIONS: Green House - Natural temperature and daylight. September-January 1995, 1996 and 1997 METHOD NARR: Young seedlings were transplanted into pots containing soil infected with Streptomyces scaea) and S. turgidiscabies (from Tokachi area) for 1995 and 1996 tests. For 1997 test, sterilized soil was mixed with S. tugidiscabies 91SY-3. Upon harvest, clones with no visible scab symptoms were saved and used in the nex rate in each year was defined as the percent clones that were visually scored zero out of all clones that set tubers. The final selection rate of each accession is the product of all 3 years with the highest cumulative score b. RESULTS NARR: In seasons 1996 and 1997, infestation was scored visually as 0=no symptoms, 1=few, small symptoms, 2=some prominant symptoms or 3=severely damaged. AUTHOR EXPLANATION: In general, mcd, rap, spl, vrn and chc showedf accessions carrying any resistance. Conversely, buk, can, ktz, mlt and oka contained clones which survived well through all three selections. The first two years had a mixture of unidentified strains while the third yen and this may have had some effect on the resistance correlations between years.

METHOD: Visual Examination CONDITIONS: Green House METHOD NARR: Accessions were propagated in a GH and tubers were harvested. They were stored at 3-4C until inoculation approximately one month later. Tubers were inoculated wither tuber using a hand-held sprayer. After 1 month, tubers were evaluated for infection by rating sporulation on the tuber surface. Sporulating patches were found and then the number of conidiophore groups per field of view showing very low or no infection in the laboratory trials were exposed to natural inoculum in storage facilities for both processing and table stock storage. RESULTS NARR: There were accessions with consistently high sporulasporulation in both the lab and storage tests. Some accessions had inconsistant results. Significant differences were found among accessions of the same species. AUTHOR EXPLANATION: Fungal sporulation, instead of disease symptoms,reening because of the great variability of periderm color and smoothness among the species, which made differentiation of natural periderm characteristics of the species from silver scurf symptom difficult. In addition,uces similar symptoms. Infection in table stock storage was lower than in processing storage which may be a function of differences in temperature.

Twelve plants of each population were planted in the fall of 2008 for winter greenhouse tuber generation. One tuber from each of 12 individuals was randomly selected. They were rinsed with distilled water and dried overnight before inoculation. Pectobacterium carotovorum isolate WPP14 (provided by Dr. Amy Charkowski, UW-Madison) was cultured on agar plates and 10 ?l of prepared bacterial suspension (1.0 ? 108 CFU/ml, OD value at 0.20, which was measured with the wavelength at 600 nm) was used as the inoculum source (Yap et al., 2004). A sterilized pipette tip was used to make a 7 mm deep hole in the middle of each tuber, avoiding lenticels. Then, the inoculum was injected into the hole using a new pipette tip. A new tip was used for each inoculation. After a 72-h incubation period in the dark at > 80% relative humidity and room temperature (23?C), each inoculated tuber was cut in half along the inoculated hole. Lesion diameter on the cut tuber was measured.

Fifteen plants per accession and three tubers per plant were evaluated for soft rot resistance. Accessions were representative of a broad geographic area and a wide range of habitats. P. carotovorum isolate WPP14 was cultured and 3 ul of prepared bacterial suspension was inoculated into each tuber in a hole with a depth of 5 mm created by a pipette tip (34). Then, the diameter of decay was measured after a 72-h incubation in the dark at 100% relative humidity and 25 degrees C. An average of the measures was calculated. Smaller measures are more resistant.

Updated Listing of Potato Species Names, Abbreviations and Taxonomic Status.

METHOD: ELISA, ISEM and Visual Examination CONDITIONS: Green House - 18h light with light intensity 150umol. Daily minimum temp 19C, maximum temp 24C. METHOD NARR: In vitro plantlets were transplanted to soil. The viruses wereplants of each clone, in each of the 2 or 3 experiments carried out for each strain, both mechanically and by graft. ELISA and ISEM were used for detection 21 and 28 days after mechanical and graft inoculation respectively.ed for PVA. AUTHOR EXPLANATION: Differences in response to inoculation by mechanical means versus grafting are noted. Temperature can affect the development of necrosis with HR rendered less effective at higher temps. Remarstance phenotyoes were determined.

METHOD: Visual Examination CONDITIONS: Green House and Field METHOD NARR: The plants were evaluated in the field for three consecutive seasons. The most susceptible entries were dropped after each planting. Water was applied ton and not sprinkled so as not to wash away the thrips. Field resistance was evaluated at 1 month, 2 months and 2.5 months of age. Entries that showed resistance in the field were re-evaluated in the GH using the same ratinumerical (1-5) system was used to correspond to a highly resistant through highly susceptible rating scheme based on degree of damage to the plant. AUTHOR EXPLANATION: It is noted that the first two field trials generated unroncentration of thrips. When insecticides are applied to inhibit unwanted insects, the thrips populations increase.

METHOD: Both and Visual Examination METHOD NARR: Accessions were mechanically inoculated with PVYntn and TMV. The plants were symptomatologically checked and ELISAs were performed.Back inoculations were carried out using Nicotiar plants. RESULTS NARR: Only one accession was immune to PVYntn infection - PI584492. None of the accessions showed local hypersensitive reactions.

METHOD: ID of phenolics CONDITIONS: Green House - 16h light at 20-26C with RH from 60-90% and 32,000 lux at soil level METHOD NARR: The contents of the heads of type A trichomes was collected. HPLC was used to detect phenolics.tivity was measured as percent transittance at 440 nm. NMR analysis was used in identification of phenolics. RESULTS NARR: Relatively few phenolics are present in the type A trichomes of ber and pld. In pld n-chlorogenicic acid oxidation activity of pld was 2-fold greater than ber. AUTHOR EXPLANATION: The presence of p-hydroxyphenylpropionic acid glucose ester in both species suggests it is an important factor in trichome mediated insect res

METHOD: Chemical Assay CONDITIONS: Green House - 16h light at 18-27C and rh between 60-90% METHOD NARR: Trichome exudates were collected from type A and B trichomes. Whole-leaf sesquiterpenes were collected and purified. ID of determined using GC-MS. The influence of extracted sesquiterpene fractions on settling behavior of M. persicae was determined using a test arena. Numbers of aphids present on each of the feeding areas were determined afterB-caryophyllene and D-Cadinene were to major components identified in type A trichomes. Two minor components were a- Copaene and E-B-Farnesene. Concentrations of sesquiterpenes (SQT) from type B trichome exudate varied conside 0.34% had a repellent effect on aphids. At 0.25% the SQTs failed to discourage settling. AUTHOR EXPLANATION: There were qualitative and quantitative differences in sesquiterpenes (SQT) from sib-mated plants, suggesting a genetic brences. Results indicate that SQTs other than E-B-farnesene alter aphid behavior. Authors hypothesize that the SQTs are not produced by type B trichome glandular cell. Rather they are readily taken up from the environmeichome tip and slowly released again.

METHOD: Chemical Assay CONDITIONS: Green House METHOD NARR: 10 seedlings of each PI were examind under a microscope to estimate trichome density. Means for trichome densities were calculated with a circular micrometer 1mm in diales of fresh foliage from mature plants were collected in order to determine presence of acetylated sucrose esters using capillary gas liquid chromatography. RESULTS NARR: Three distinct classes of sucrose esters were deteignificance of the different classes in relation to species boundaries is discussed.

METHOD: ELISA, Western CONDITIONS: Green House - 14-16h light METHOD NARR: Trichome exudate was collected and used in ELISA and Western Blotting tests. The ELISA was developed to detect and quantify PPO in type A trichomes and pnm. Hybrids between ber and tbr were generated and subjected to the same tests. RESULTS NARR: An individual trichome yields a detectable, linear ELISA signal, with saturation occuring at 40-50 trichomes. One ber type A t possess ~1ng of PPO. Genetic background appears to influence PPO expression. AUTHOR EXPLANATION: Trichome density vs. PPO quantity varies with leaf age and implications are discussed.

Accessions were field grown at Hancock, Wisconsin HARS station from early June – early Oct of 2021 using standard crop inputs that resulted in very high tuberization for all commercial US and European cultivars growing as checks in the same field. They were evaluated as 10 hills each of seedling transplants.

Study Name: Tuberization. Experiment Type: Field FIELD Study Year: 1992 Year started: 05/06/1992 Year ended: 10/28/1992

Tubers were planted at the Hancock Research Station in the spring of 2015 - two hills of each clone were grown. Hills were dug on September 21, field pictures were taken of a single hill and tuber samples were collected and brought back to the Sturgeon Bay Research Station to be evaluated for tuber size, tuber shape, tuber skin color, tuber flesh color and tuber skin texture.

Samples were collected from 97 populations of the wild potato S. stoloniferum (previously fendleri) in the following seven mountain ranges of the southwest USA over 7 years, 2004-2010: Chiricahua (CHI), Huachuca (HUA), Rincon (RIN), Guadalupe (GUA), Pinaleno (PIN), Santa Catalina (CAT), and Santa Rita (RIT). These and previous samples were compared with AFLP markers to determine which ranges have the most genetic richness. A total of 2,079 bands were polymorphic over all populations, and 1,256 were polymorphic among ranges. Of these 1,256 bands, 279 occurred in only one range (= unique). The number of unique bands for each population was determined and noted.

METHOD: Chemical Assay CONDITIONS: Field METHOD NARR: Seedlings were planted in rows and subjected to 2 Nitrogen treatments (0kg and 225kg N per ha). Nitrogen as ammonium nitrate was applied on three occaisions. Tubers, roots, shoots and fruits were collected seperately. After washing, the samples were oven-dried at 60C and the dry weight of the separate parts recorded. Total tissue N was determined conductimetrically, following a salicylic Kjeldahl nitrogen digestion procedure. Nitrogen uptake efficiency and percent N recovery were calculated. Wild accessions were ranked based on total dry matter accumulation and then categorized based on an efficiency index (E). RESULTS NARR: Total plant dry weight, N content and N concentration were significantly affected by N fertilizer and genotype. Nitrogen uptake efficiency was calculated as follows: NUE = (PN/SN) x (TDW/PN) = (TDW/SN) where (PN/SN) is (total plant N content/fertilizer N) and (TDW/PN) is (total dry weight of all plant parts/total plant N content). More simply, N use efficiency = (Uptake efficiency) x (Utilization efficiency) = (Yield efficiency). Efficiency index (E) = (TDWPN - TDWZN)/225 where TDWPN = total dry weight at 225kg N per ha and TDWZN = total dry weight at 0kg N per ha. If TDWZN greater than or equal to 300.00g, accession is Good Forager. If E greater than or equal to 10 g per g, accessions were Good Responders. AUTHOR EXPLANATION: Dry weight was found to be a good indicator of of N uptake. Poor tuber production by wild types was most likely due to the lack of short days. Authors suggest that higher N recovery by wild species could be due to deeper penetrating, denser and more branched root systems.

METHOD: Chemical Assay CONDITIONS: Field METHOD NARR: Seedlings were planted into rows and subjected to 2 Nitrogen treatments (0kg and 225kg N per ha). Nitrogen as ammonium nitrate was applied on three occaissions. Tubers, roots, shoots and fruits were collected seperately. After washing, the samples were oven-dried at 70C and the dry weight of the seperate parts recorded. Total tissue N was determined conductimetrically, following a salicylic Kjeldahl nitrogen digestion procedure. Nitrogen uptake and utilization efficiencies were calculated. Year 1 RESULTS NARR: Nitrogen uptake efficiency was calculated as follows: NUE = (PN/SN) x (TDW/PN) = (TDW/SN) where (PN/SN) is (total plant N content/fertilizer N) and (TDW/PN) is (total dry weight of all plant parts/total plant N content). More simply, NUE is (Uptake efficiency) x (Utilization efficiency) = (Yield efficiency). Efficiency of utilization (per Siddiqi & Glass) is calculated as follows: E = (TDW/PN) x TDW = TDWsquared/PN. AUTHOR EXPLANATION: An uncontrollable outbreak of CPB occured in 1994 severely affecting susceptible cultivars but not resistant wild species. Dry weight partitioning was closely associated with the level of domestication of the potato species. Poor tuber production by wild types is most likely due to the lack of short day conditions.

METHOD: Chemical Assay CONDITIONS: Field METHOD NARR: Seedlings were planted into rows and subjected to 2 Nitrogen treatments (0kg and 225kg N per ha). Nitrogen as ammonium nitrate was applied on three occaissions. Tubers, roots, shoots and fruits were collected seperately. After washing, the samples were oven-dried at 70C and the dry weight of the seperate parts recorded. Total tissue N was determined conductimetrically, following a salicylic Kjeldahl nitrogen digestion procedure. Nitrogen uptake and utilization efficiencies were calculated. Year 2 RESULTS NARR: Nitrogen uptake efficiency was calculated as follows: NUE = (PN/SN) x (TDW/PN) = (TDW/SN) where (PN/SN) is (total plant N content/fertilizer N) and (TDW/PN) is (total dry weight of all plant parts/total plant N content). More simply, NUE is (Uptake efficiency) x (Utilization efficiency) = (Yield efficiency). Efficiency of utilization (per Siddiqi & Glass) is calculated as follows: E = (TDW/PN) x TDW = TDWsquared/PN. AUTHOR EXPLANATION: An uncontrollable outbreak of CPB occured in 1994 severely affecting susceptible cultivars but not resistant wild species. Dry weight partitioning was closely associated with the level of domestication of the potato species. Poor tuber production by wild types is most likely due to the lack of short day conditions.

Accessions were planted under 3 soil fertility regimes and assayed for tuber yeild, dry matter content, and true protein content. A response index was used to characterize the behavior of each genotype to fertilizer application. The soil regimes are as follows: F0 = sub-optimal (0kg N, 0kg P, 0kg K per ha); F1 = standard (120kg N, 35kg P, 67kg K per ha); F2 = super-optimal (160kg N, 44kg P, 84kg K per ha). Yield and protein content increased with increased applications of fertilizer. Dry matter decreased with increased fertilizer dose, but when the fertilizer dose was further increased, dry matter increased. These results indicate that performance and responsiveness to fertilizers are linked and hence will not be easily amenable to independent alteration.

Accessions were planted under 3 soil fertility regimes and assayed for tuber yeild, dry matter content, and true protein content. A response index was used to characterize the behavior of each genotype to fertilizer application. The soil regimes are as follows: F0 = sub-optimal (0kg N, 0kg P, 0kg K per ha); F1 = standard (120kg N, 35kg P, 67kg K per ha); F2 = super-optimal (160kg N, 44kg P, 84kg K per ha). Yield and protein content increased with increased applications of fertilizer. Dry matter decreased with increased fertilizer dose, but when the fertilizer dose was further increased, dry matter increased. These results indicate that performance and responsiveness to fertilizers are linked and hence will not be easily amenable to independent alteration.

Accessions were planted under 3 soil fertility regimes and assayed for tuber yeild, dry matter content, and true protein content. A response index was used to characterize the behavior of each genotype to fertilizer application. The soil regimes are as follows: F0 = sub-optimal (0kg N, 0kg P, 0kg K per ha); F1 = standard (120kg N, 35kg P, 67kg K per ha); F2 = super-optimal (160kg N, 44kg P, 84kg K per ha). Yield and protein content increased with increased applications of fertilizer. Dry matter decreased with increased fertilizer dose, but when the fertilizer dose was further increased, dry matter increased. These results indicate that performance and responsiveness to fertilizers are linked and hence will not be easily amenable to independent alteration.

Study Name: Resistance to Verticillium Wilt. Experiment Type: Field FIELD Study Year: 1983 Year started: 05/15/1983 Year ended: 12/14/1983. Ten seedlings were inoculated by putting five milliliters of a Verticillium dahliae inoculum into the root zone with a syringe. Two days after inoculations, the plants were put into the field. Accessions were rated by squeezing the sap out of a potato stem into a petri dish and adding a diagnostic medium. Four individual plants were then analyzed for Verticillium propagules. The average number of propagules were computed for each accession.

Study Name: Resistance to Verticillium Wilt. Experiment Type: Field FIELD Study Year: 1984 Year started: 05/15/1984 Year ended: 12/10/1984. Ten seedlings were inoculated by putting five milliliters of a Verticillium dahliae inoculum into the root zone with a syringe. Two days after inoculations, the plants were put into the field. Accessions were rated by squeezing the sap out of a potato stem into a petri dish and adding a diagnostic medium. Four individual plants were then analyzed for Verticillium propagules.

Study Name: Resistance to Verticillium Wilt. Experiment Type: Field FIELD Study Year: 1983 Year started: 05/17/1983 Year ended: 09/15/1983 Comment: Wilt readings were made in early September and stem sections were taken in order to determine whether or not symptomless infections had occurred. Each accession was given a wilt r esistance percentile from 0 to 100.

Study Name: Resistance to Verticillium Wilt. Experiment Type: Field FIELD Study Year: 1984 Year started: 09/01/1984 Year ended: 01/12/1985. Seedlings were transplanted into Verticillium dahliae infested soil (470 colony forming units/g soil mix). Criteria to assess resistance were 1) time of appearance of symptoms, 2) fraction of individuals showing symptoms and severity of symptoms, and 3) fraction of individuals with stems colonized by Verticillium dahliae. The accessions were given an index score (0-10) based on these criteria.

Study Name: Resistance to Verticillium Wilt. Experiment Type: Field FIELD Study Year: 1984 Year started: 04/01/1984 Year ended: 12/12/1984. Two different methods were used to inoculate the test accessions. Method A: An inoculum of Verticillium dahliae and Verticillium ablo-atrum was placed in a ten centimeter trench along side the test seedlings and the trench was covered. Method B: Same as method A except the roots were mechanically wounded before inoculation. The accessions were evaluated after the first trace of wilt was detected and were given a wilt rating (0-10).

Study Name: Resistance to Verticillium Wilt. Experiment Type: Greenhouse GREENHOUSE Study Year: 1984 Year started: 12/05/1984 Year ended: 12/12/1985. After three weeks, seedlings were removed from the plastic trays and roots were clipped with a scissors. One milliliter of Verticillium dahliae inoculum was pipetted onto the cut area. The plants were re-potted and visual evaluations were made of each plant at two week intervals for eight to 14 weeks. Each accession was given a visual rating (0-3).

Study Name: Resistance to Verticillium Wilt. Experiment Type: Greenhouse GREENHOUSE Study Year: 1984 Year started: 05/29/1984 Year ended: 01/14/1985. Plants were inoculated by taking the three week old seedlings out of the pots, damaging the roots, and pipetting an inoculum of Verticillium albo-atrum onto the wounded roots. Twenty-one days after inoculations, evaluations were made of the percent defoliation (F1) and the percent wilt (F2).

METHOD: Visual Examination CONDITIONS: Growth Chamber - 14h light at about 25 klux, and 23C METHOD NARR: Plants were inoculated by dipping roots in V. dahliae microsclerotia suspension for 15 minutes. Plant height, survival andms were evaluated every month for 2 months starting 16 days after inoculation. Fungal samples were extracted from the stems 110 days after inoculation. The number of CFU was scored and calculated per gram of fresh tissue.nalysis, determination of ploidy level, morphology and male fertility, and frost tolerance were also evaluated. RESULTS NARR: After 1 month cmm showed some reduction in growth but later recovered. Very limited fungal coloniz

METHOD: Visual Examination and Colony Counts CONDITIONS: Green House METHOD NARR: Wild species were tested for resistance to both V. dahliae and V. albo-atrum. Seedlings were inoculated at 3 weeks through root injury by cuttingil and pouring 5ml of inoculum into the trench. Visual assessments were done every week for 100 days. RESULTS NARR: Significant negative associations were observed between colony counts and percent tuberization and tubergence, % emergence and root volume showed negative associations with colony counts, but not at significant levels. Unlike earlier reports, resistance to V. albo-atrum does not neccessarily indicate resistance to V. dahliae. AUggests that visual disease rating can be an accurate measure of verticillium wilt infection relative to mean colony counts. Data suggests that the inheritance to Verticillium may be polygenic and complex. Wild species used in this st of resistance other than immature plant resistance.

METHOD: Both CFU counts and Visual Examination CONDITIONS: Green House - 16h light 18-22C METHOD NARR: Tubers were planted in the GH and inoculated with V. albo-atrum 4 weeks after planting. Root injury was accomplished by removthe root ball and inoculation by submerging the remaining portion of the root ball for 10 min. in spore suspension. Visual examination started 4 weeks after inoculation and continued weekly for 4 weeks. Vascular colonizatiosed by counting total CFU in 0.1ml aliquot of plant sap in those genotypes where visual assessment showed resistance or tolerance. RESULTS NARR: No wilt symptoms were observed in resistant plants while susceptible plants expeorosis, necrosis and death. Extensive stem colonization by the pathogen occured in most of the plants rated resistant. AUTHOR EXPLANATION: Results indicate that tolerance is more common than resistance. Tolerance is defined as noh significant stem invasion. Resistance is defined as no symptoms and very low stem invasion. Visual symptom expression and degree of stem invasion by V. dahliae are poorly correlated.

METHOD: Both Leaf Disc Bioassay and Visual Examination CONDITIONS: Green House - 16-24C, March-May 1987 METHOD NARR: Seedlings were transplanted into pots containing V. dahliae inoculum using an 'inoculum sandwich' technique. The plants were observed for symptoms for up to 6 weeks after inoculation. Acetone precipitates of the crude toxin of the V. dahliae isolates were prepared. The reaction of clones to the toxin was evaluated using an excised leaf bioassay. Leaves of 4-6 week old plants were excised and maintained in SDW. The intercellular spaces of the tissue between the prominent lateral veins were injected with the toxin. The disks were evaluated after 72 hours. RESULTS NARR: A 0-7 scale was used to evaluate the symptoms observed in the plants with 0 = no symptoms and 7 = plant totally wilted. For the leaf bioassay a 0-4 scale was used where 0 = no chlorosis or necrosis, 1 = chlorosis of the injected area, 2 = chlorosis and isolated necrotic spots in the injected area, 3 = necrotic areas partly coalescing, 4 = necrosis of all the injected areas and yellowing of the adjoining tissue. AUTHOR EXPLANATION: The results do not support the use of toxin as a screening tool for wilt resistance. There was a highly significant correlation between the level of wilt susceptibility and the degree of colonization by V. dahliae.

Study Name: Plant vigor. Six plants per accession were planted in the field during the summer of 1992. Each accession was compared to the other accessions within the species group and was given a vigor score (0-dead to 5-highest vigor within species).

Study Name: Plant vigor. Six plants per accession were planted in the field during the summer of 1994. Each accession was compared to the other accessions within the species group and was given a vigor score (0-dead to 5-highest vigor within species).

Study Name: Plant vigor. Six plants per accession were planted in the field during the summer of 1995. Each accession was compared to the other accessions within the species group and was given a vigor score (0-dead to 5-highest vigor within species).

Study Name: Plant vigor. Six plants per accession were planted in the field during the summer of 1996. Each accession was compared to the other accessions within the species group and was given a vigor score (0-dead to 5-highest vigor within species).

Study Name: Plant vigor. Six plants per accession were planted in the field during the summer of 1997. Each accession was compared to the other accessions within the species group and was given a vigor score (0-dead to 5-highest vigor within species).

Study Name: Plant vigor. Six plants per accession were planted in the field during the summer of 1998. Each accession was compared to the other accessions within the species group and was given a vigor score (0-dead to 5-highest vigor within species).

The study included between one and seven accessions of each of 31 ingroup (sect. Petota) and three outgroup (sect. Etuberosum) species. Half of the seedlings of an accession were placed in one flat and half in another flat to construct two replications. Seedlings were inoculated 2 to 3 wk after transplanting. Flats were not disturbed until the fourth day after inoculation. Four days after inoculation, the dome was reremoved from each flat and each plant was scored for its response to the fungus. A plant was given a score of one if it was alive and zero if the fungus had caused the stem to collapse and the plant to die. This process was repeated every day for 14 d. A survival score was determined for each plant on the basis of the number of days it remained alive. The mean score is the average of all plants evaluated. High scores are more resistant.

METHOD: Reproductive Efficiency CONDITIONS: Green House METHOD NARR: Test were carried out twice, with slightly different inoculation methods. Seedlings were inoculated with either crushed cysts or whole cysts. At 10-12 weeks pwilt. Cysts were counted and reported as a ratio of final population to inoculation number. RESULTS NARR: A Pf/Pi ratio of less than 2 was regarded as resistant. AUTHOR EXPLANATION: Geographical distribution of resistant species is discussed.

METHOD: Visual Examination CONDITIONS: Green House METHOD NARR: Four viruses, 1 fungus and 1 nematode were used to test for resistance. Tubers were used except for non-tuber-bearing accessions. Pot tests were performed with infers as replicates. Each pot was inoculated with 30 cysts giving an infestation density of 10-20 juvenals/gram of soil. Accessions with no visible females were processed using the Fenwick can. Resistant = <5 cysts. Partialcontrol. Accessions identified as resistant were retested to confirm resistance. RESULTS NARR: Over 70% of all evaluated accessions carried one or more resistances. AUTHOR EXPLANATION: All tubers obtained from one accessied tuber production under given conditions. Therefore, the results can not be generalized to the whole accession. Patterns of resistance are discussed. It is noted when the results obtained in this study do not match those of previonations are offered.

S. bulbocastanum germplasm (all 53 populations available in 2012) were obtained from the US Potato Genebank in Sturgeon Bay, WI. Fifty plants, one from each germplasm population, were placed into each of two dome cages. Each cage was infested with 100 adult potato psyllids, which were evenly distributed throughout the cages. Twenty-one days after releasing adults, the numbers of eggs, early instars (first through third instars), and late instars (fourth and fifth instars) present on each plant were counted. The 21-day duration was chosen because the eggs oviposited on the day of adult releases should reach the fifth instar by this time, but not yet molt to adult (Tran et al. 2012). The experiment was repeated three times (trial) with different cohorts of plants and insects for a total of 6 cages. The large number of plant populations included in the assays prevented meaningful statistical comparisons in susceptibility to psyllids among germplasm populations. Instead, plant susceptibility to B. cockerelli was ranked based on the mean numbers of eggs, early instars, and late instars observed on the plants at the end of the experiment. The lower and upper quartiles associated with the mean numbers of each insect age class, regardless of germplasm population, were calculated using SAS 9.3 (SAS Institute 2012). The least susceptible populations were identified as those with mean numbers of eggs, early instars, and late instars each below the lower quartile of their respective insect age class. The most susceptible populations were identified as those with mean numbers of eggs, early instars, and late instars above the upper quartile of their respective age class. Germplasm that supported numbers of at least one insect age class between the lower and upper quartiles were ranked as having intermediate susceptibility to B. cockerelli.

S. verrucosum germplasm from all 41 populations that were available in 2012 was obtained from the US Potato Genebank in Sturgeon Bay, WI. One plant from each germplasm population was placed into each of 6 dome cages (60×60×60 cm; MegaView Science Co. Taichung Taiwan) so that each cage contained a total of 39 plants. One hundred adult potato psyllids were evenly distributed throughout each cage. After 21 days, the numbers of eggs, early instars (first through third), and late instars (fourth and fifth) present on each plant were counted. Plant susceptibility to potato psyllid was ranked based on the mean numbers of eggs, early instars, and late instars observed on the plants at the end of the experiment. The lower and upper quartiles associated with the mean numbers of each insect age class, regardless of germplasm population, were calculated using SAS 9.3 (SAS Institute 2012). The least susceptible populations were identified as those with mean numbers of eggs, early instars, and late instars each below the lower quartile of their respective insect age class. The most susceptible populations were identified as those with mean numbers of eggs, early instars, and late instars each above the upper quartile of their respective age class. Germplasm that supported numbers of at least one insect age class between the lower and upper quartiles were ranked as having intermediate susceptibility to potato psyllid.