Cytogenetical studies in wheat iv. Chromosome location and linkage studies involving thePM2 locus for powdery mildew resistance

Summary The genePm2 conditioning resistance to powdery mildew in the cultivar Ulka was located on chromosome 5D by monosomic analysis. It showed genetic segregation independent of geneLr3 conditioning resistance to leaf rust on the same chromosome. Results of telocentric mapping demonstrated thatLr1 was on the long arm of 5D whereasPm2 was very close to the centromere on this arm or, more likely, on the opposite arm. Evidence from chimaeric sectoring favoured the latter alternative.