Study on the presence of resistance gene loci to yellow, stem and leaf rust diseases using molecular markers in pre-released wheat lines

Yellow، leaf and stem rusts are among the most devastating diseases of wheat in Iran and worldwide. The use of resistant cultivars is the most effective and economic approach to control these diseases. To date، a significant number of molecular markers linked to the resistance loci to these diseases have been identified. In this study، pre-released wheat lines of four major wheat climate zones of Iran were evaluated for the presence or absence of molecular markers linked to 11 resistance loci including Lr46/Yr29/Pm39، Lr34/Yr18/Pm38، Lr67/Yr46، Sr2/PBC، Sr24/Lr24، Sr26، Sr31/Yr9/Lr26، L21، Sr38/Yr17/Lr37، SrCad and Lr29. The results showed that Lr46/Yr29/Pm39، Lr34/Yr18/Pm38 and Lr67/Yr46 loci existed in four and five genotypes، respectively، while Sr31/Yr9/Lr26 and Sr38/Yr17/Lr37 loci existed only in one genotype. The remaining genotypes did not possess markers linked to resistance loci tested in this study. The results showed that the frequency of presence of these loci in pre-released lines is low and، thus، lines possessing the resistance loci should be incorporated in wheat breeding programs in order to increase the frequency of the resistance genes in new cultivars.