Exploring Iranian wheat landraces for stripe rust resistance genes and validation of selected genes using molecular markers

Abstract Puccinia striiformis Westend. f. sp. tritici Eriksson (Pst), the causal agent of stripe rust, is known as an important and destructive pathogen that causes critical wheat losses in many parts of the world. Employing effective resistant genotypes is a safe and operative strategy to combat the disease. Iran is located in the Fertile Crescent, the co-epicentre of wheat and its biotic stresses. Iranian wheat landraces may carry important sources of resistance against rust diseases. Adult plant reactions of 467 Iranian wheat landraces to stripe rust were studied in two cropping seasons in Fars province. One hundred and six landraces showed acceptable levels of resistance and were selected for further seedling and molecular studies based on their lower infection type, coefficient of infection (CI) and average coefficient of infection (ACI). The presence of Yr4, Yr10, Yr24 and Yr32 resistance genes were postulated using 10 different Pst isolates including PstS10, PstS7, PstS3, PstS2+V27, PstS11, PstS8, PstS13, PstS6, PstS0 and Me2018 under greenhouse conditions. Field and greenhouse reactions of near-isogenic lines reconfirmed the presence of the studied Yr resistance genes in 20 genotypes. Moreover, Xcfb3530 150 , Xpsp3000, Xgwm11, and Xwmc198 SSR markers were employed to identify and validate the presence of the above corresponding genes. The presence of Yr4, Yr10, Yr24 and Yr32 resistance genes in five (1.07%), 10 (2.14%), five (1.07%) and seven (1.5%) experimental landraces were confirmed, respectively. Six genotypes are harbouring more than one resistance gene. These effective resistance sources can be employed in national and international breeding programs.