Narrative
Soft red winter wheat translocation line (7DS.7DL-7EL) having the distal 3/4 of chromosome 7EL, determined by DNA marker analysis, from Thinopyrum intermedium with resistance to yellow dwarf viruses BYDV-PAV and CYDV-RPV. After the second cross to Caldwell a yellow dwarf resistant, low virus titer by ELISA testing, F4 plant, 2n=44, was identified and 151 seeds from self pollination of the 2n=44 plant were irradiated by gamma rays using 60 CO. An M4 putative translocation plant, low ELISA value and 2n=42, was crossed to an F5 plant with parentage: Oasis/3/Clark*4/Ning 7840//Clark/Roazon, and the F1 was crossed to Patterson. After the cross to Patterson, F2 and F4 plants were selected in a pedigree breeding method. This germplasm line is the progeny of a single F4 plant. ELISA values in a 4-replicate test, 14 d after infestation with aphids viruliferous for BYDV-PAV and CYDV-RPV, was 0.095 and for Abe 0.516, LSD 0.05=0.264. Yellow dwarf symptom score (0-9, 0=no symptoms to 9=severe leaf discoloration and plant stunting) in replicated field nurseries in 2002 at Lafayette, Indiana, with natural yellow dwarf viruses infection in wheat seedlings in fall 2001 was 0.5 and for P29, Abe and Caldwell 0.5, 7.8, and 5.2, respectively, LSD 0.05=0.7. Resistance to Stagnospora nodorum blotch, typically averaging a score of 4 (0-9, 0=no symptoms to 9=severe disease in glumes), has Lr37, Yr17 and Sr38, powdery mildew (Blumeria graminis) develops more slowly than susceptible wheat lines, typically scored at 2-4 (0-9, 0=no lesions to 9=severe mottling and plant stunting). Flowering date in Indiana similar to Patterson. Anthers yellow, awnlets typically 3-5 mm long.