Identification of Wheat Rust Resistance Genes (Lr26, Sr31, Yr9) Using Specific PCR

The chromosomal arm 1RS of rye (Secale cereale L.) is a valuable resource for improving the properties of wheat (Triticum aestivum L.) which has been translocated with the short arm of a wheat group-1 chromosome (1AL. 1RS، 1BL. 1RS، 1DL. 1RS). This arm carries rust resistance genes; Lr26 for leaf rust (Puccinia triticina)، Sr31 stem rust (P. graminis) and Yr9 for stripe rust (P. striiformis). These genes were located 6. 6 cM from the Sec-1. This close linkage has been used as a marker for identification of rust resistance genes. In this study، the presence of Sec-1 was examined in 66 Iranian cultivars and 70 abroad regional accessions، using rye-specific primer “O-SEC”. The rust resistance gene by the presence of Sec-1 was verified in 15 (23%) Iranian cultivars and 2 (3%) abroad accessions. Moreover، because of the rye-specific primer can distinguish between 1AL. 1RS and 1BL. 1RS translocations، the presence of these genes were identified in 14 (21%) cultivars and 2 (3%) abroad accessions in chromosome 1B. Also among all cultivars and accessions، the presence of the resistance genes was verified in chromosome 1A of «Sholeh» cultivar (1. 5%). On the whole، the presence of rust resistance genes in Iranian wheat cultivars appeared to be better than abroad wheat accessions. This is because many Iranian wheat materials are commercial cultivars and in their pedigree have cultivars carrying rust resistance genes. The results of this study can be used for the production of new wheat cultivars in breeding programs.