Molecular Cytogenetics Study On Derivatives Of Triticum Aestivum L. And S.Cereale L. With Resistance To Powdery Mildew

Wild relatives of wheat are one of the large gene banks. The introduction of genetic germplasm from wild relatives has an important effect on wheat. S. cereale, one of the related species of wheat, is the most soon and the most successful species to improve wheat in Triticeae. In this paper, wheat-rye derivatives of wheat and rye are identified by means of morphological character recognition, cytogenetic analysis and molecular test including chromosome C-banding and simple sequence repeat (SSR). The results are as following: 1. The wheat-rye derivatives are grouped into 2 types by means of chromosome numbers of root tip cells (RTC) and chromosome configurations of pollen mother cells (PMC). The karyotype of first group (N9436-0-2-11-8-1,N9436-0-2-29-9) was 2n=44=22II, and the second group (N9436-0-1-5-5,N9436-0-2-29-2-1) was 2n=42=21II. N9436-0-1-5-5 has dark green leaves, spindle spikes and medium wax powdery. N9436-0-2-11-8-1 also has dark green leaves, spindle spikes and light wax powdery. And the difference is the first one has short awn, while the second one has long awn. N9436-0-2-29-2-1 and N9436-0-2-29-9 have purple stems, purple leaves, spindle spikes and heavy wax powdery. And the difference is the first one has short awn, while the second one only has top awn. 2. Identification of resistance to powdery mildew indicated that N9436-0-1-5-5 and N9436-0-2-11-8-1 similar to rye were immune to powdery mildew, while N9436-0-2-29-2-1 and N9436-0-2-29-9 had medium resistance to powdery mildew 3. Giemsa C-banding indicted that N9436-0-1-5-5 was wheat-rye 1R disomic substitution line, N9436-0-2-11-8-1 wheat-rye 1R disomic addition line, N9436-0-2-29-2-1 6R disomic substitution line, N9436-0-2-29-9 6R disomic addition line. 4. SSR results showed that N9436-0-2-11-8-1 possessed 1R of rye chromosome and N9436-0-2-29-2-1 possessed rye genetic germplasm of 1R and 2R.