Development Of A Molecular Marker Related To Stripe Rust Resistance Gene In Multi-Gene Pyramiding Of Wheat Line YW243

The wheat line YW243 was developed by cross between disease resistant line and another culture. It was also a line resistant to powdery mildew, stripe rust and barley yellow dwarf virus. It carries a new yellow rust gene conferring resistance to CY31. In the present study, the resistance pattern of a F₂ population (120 individuals) derived from cross of YW243 and CS was analyzed through inoculation of CY31 isolate. The pattern results showed the R/S segregation ratio fits 3:1, suggesting that the gene of interest possesses a single-dominant-gene inheritance mode. Combining bulkd segregant analysis (BSA) and AFLP techniques, this new gene was tagged. Since bad agricultural characters of YW243, it wasn't used derectly in production. By YW243 crossed with some elite varieties with good characters of agriculture, Four lines with high yield and good resistance were obtained: CB031, CB032, CB034, CB035. In order to evaluate YW243, these new lines were analyzed and compared the resistance, quality, yield with YW243 and the backcrossed parents.Some multi-resistance gene lines were studied by molecular marker-assisted selection. The resulted indicated that:1. Combining bulkd segregant analysis (BSA) and AFLP techniques, a total of 256 AFLP primer pairs were used to screen in YW243, Chinese spring, the R pool and the S pool, about 2.7% primer pairs showed polymorphism between R and S. Linkage analysis in F2 population with these primer pairs, the primer combination of M54/E63 and M54/E64 were proved to be tightly linked to the gene of interest with genetic distances being 9.27cM.2. Four new lines: CB031, CB032, CB034, CB035 were analyzed and compared the resistance, quality, yield with YW243 and the backcrossed parents. The results indicated that the wheat line YW243 has good value , since its good characters could be inherited, while its bad characters could be improved. It was valuable in wheat breeding.3. The Co- conferring PCR markers of the powdery mildew resistance gene Pm4 , Pm13, Pm21, the SCAR marker of the B YDV resistance gene Bdv2 ,and SSR marker Xgwm501 were used to screen 04P breeding population , several plants were found to pyramid these genes.