Screening of bread wheat genotypes for identification of novel stripe rust resistance genes using molecular markers

Stripe Rust, caused by Puccinia striiformis Westend f. sp. tritici , is an important fungal disease of wheat worldwide. In this study, 41 wheat genotypes from various institutes across India were screened for adult plant resistance (APR) in field trials, and the presence of effective stripe rust resistance genes was evaluated in the laboratory using ten molecular markers.The bread wheat variety Agra local was used as a susceptible control. Molecular characterization studies revealed that the gene Yr 2 was found in 29 entries, Yr5 in 15 entries, Yr9 in 7 entries, Yr10 in 18 entries, Yr15 in 18 entries, Yr17 in 12 entries, Yr18 in 29 entries, Yr36 in 21 entries, Yr40 in 31 entries while Yr65 was absent in all the entries. The genotypes PBW780 and High Rainfall Wheat Screening Nursery (HRWSN) line 2105 had seven Yr genes conferring resistant phenotypes, suggesting that these were excellent sources of effectual stripe rust resistance. The coefficient of infection showed adequate genotypic variations for rust severity, 41 genotypes showed year-specific responses, suggesting strong G × E interactions.