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 F 2 and F 3 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 F 3 population of 120 families derived from the cross Kolibri ( Pm3/Gli-A1a/rg3 ) × F 10 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 .