Study on presence of stem rust resistance gene Sr2 in the Iranian varieties and elite wheat lines by using molecular markers

Stem rust of wheat caused by Puccinia graminis is known as one of the most important and prevalent diseases of wheat worldwide. Deployment of stem rust resistance genes such as Sr24, Sr26, Sr31, Sr36 and Sr38 in wheat cultivars in the last decades of 20th century dramatically reduced damaged caused by this disease. One of the durable resistance genes that controlled stem rust during this period was Sr2 which has been transferred to bread wheat from Triticum turgidum. Sr2 is a non-race specific resistance gene with slow rusting effect which confers resistance at the adult plant stage. In recent years, molecular markers which are tightly linked to Sr2 have been identified and are widely used in many countries. In this study, presence/absence of Sr2 in some of the Iranian varieties and elite wheat lines was tested using a SSR marker gwm533, and a CAPS marker. Results indicated that from 188 studied genotypes, only 16 genotypes had linked alleles to Sr2 genes. Results of this study also showed that the newly identified CAPS marker is more precise marker compared to SSR marker gwm533 to detect Sr2 gene.