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.