Characterization of powdery mildew resistance and linkage studies involving the Pm3 locus on chromosome 1A of common wheat (Triticum aestivum L.).

Genetic characterization of a new powdery mildew resistance gene in a common wheat line ATRI3004/79 was conducted by employing a set of Blumeria graminis tritici isolates collected from Europe. Monosomic analysis revealed that a major resistance gene is located on chromosome 1A. Allelism tests of the F2 and F3 populations with other previously known genes on 1A showed that the resistance gene in ATRI3004/79 is closely linked to the Pm3d resistance gene in the German cultivar Syros, whereas it segregated independently from Pm25. Based on its distinct disease response pattern and close linkage to the Pm3 locus, this new resistance gene is tentatively designated PmH1A. A genetic linkage map was constructed for the powdery mildew gene Pm3d, the red glume color gene Rg3, and the gliadin gene Gli-A1 on chromosome 1A, based on data from a F3 population of 120 families derived from the cross Kolibri (Pm3/Gli-A1a/rg3) × F10 Strela (pm3/Gli-A1f/Rg3). Close linkage to an easily visualized morphological character such as red glume color may facilitate the selection of the resistance gene PmH1A.