[Establishment of wheat-rye addition lines and De Novo powdery mildew resistance gene from chromosome 5R]

The F5 plants derived from octoploid triticale × common wheat were investigated by FISH methods using repetitive DNA sequences pAS1 and pSc119.2 as probes. The disease resistance of these plants was also screened and evaluated in the field. The 1R, 2R, 3R, 4R, 5R, 6R and 7R monosomic addition lines and 1R and 2R disomic addition lines were found. The occurrence frequencies of chromosomes 1R and 4R addition lines were higher than that of chromosomes 2R, 3R, 5R, 6R, and 7R addition lines in the high generation screened. The 5R and 6R monosomic addition lines were immune to powdery mildew. The chromosome 5R in this study might carry new powdery mildew resistance gene(s). In addition, the preferential elimination of chromosome 4B was observed in several plants.