Powdery Mildew and Leaf Rust Resistance in Winter Wheat Germplasm Lines.
Judd Maxwell1, Christina Cowger1, David Marshall2, James Kolmer3, Gina Brown-Guedira2, Jeannette Lyerly1, and J. Paul Murphy4. (1) North Carolina State University, North Carolina State University, 1243 Teakwood Pl, Raleigh, NC 27606, (2) USDA-ARS, USDA-ARS, Raleigh, NC 27695-7616, (3) USDA-ARS Cereal Disease Lab, St. Paul, MN 55108, (4) Box 7629, North Carolina State University, North Carolina State University, 840 Method Road Unit 3, Raleigh, NC 27695
Powdery mildew (Blumeria graminis DC. f. sp. tritici Em. Marchal) and leaf rust (Puccinia triticina) are two economically important diseases of common wheat (Triticum aestivum L.). The genetic characterization of three wheat germplasms, developed by the North Carolina State University Small Grains program, revealed three potentially new sources of powdery mildew resistance and a new source of leaf rust resistance. F2 derived families from the crosses NC06BGTAG12 (NCAG12) x ‘Jagger', NC06BGTAG13 (NCAG13) x ‘Jagger' and NC97BGTAB10 x ‘Saluda' were used to evaluate the genetic control of powdery mildew resistance in the three NC lines. Greenhouse evaluations revealed that one major gene in each line controlled the resistance to powdery mildew. Bulk segregant analysis (BSA) indicated that genes in both NCAG12 and NCAG13 were located on the long arm of chromosome 7A. Pm37 and the Pm1 series have also been mapped to this region of the wheat genome. However, detached leaf assays suggested that these resistance genes are different than Pm37, but further test need to be conducted to determine if they are different than the Pm1 alleles. Leaf rust evaluations revealed monogenic resistance in NCAG12, which has been shown to be different than the Lr18 and Lr50, two other T. timpoheevii derived leaf rust resistance genes.