شناسایی جایگاه‌های ژنی مقاومت به بیماری‌های زنگ سیاه و زنگ قهوه‌ای در برخی از نمونه‌های بومی گندم

Wheat stem and leaf rusts caused by the fungal pathogens Puccinia graminis f. sp. tritici (Pgt) and Puccinia triticina (respectively) are among the most devastating diseases of this crop, worldwide. Utilization of genetic resistance capability and thereby production of resistant cultivars is considered as the most reliable control method of wheat rusts. Identification of rust resistance sources as well as the involved resistance genes is prerequisite for obtaining resistant cultivars and achieving sustainable resistance to wheat rusts. Molecular markers have been identified for a significant number of stem and leaf rust resistance genes/loci. In this study, a number of 40 wheat landraces already field screened as possessing suitable agronomic characteristics, were studied for presence of the five seedling resistance genes/loci Sr39/Lr35, Sr31/Yr9/Lr26/Pm8/Pm17, Sr26, Sr24/Lr24 and Sr22 using the linked molecular markers. Based on our results the Sr39/Lr35 and Sr31/Yr9/Lr26/Pm8/Pm17 loci were tracked in only one and five wheat landraces, respectively. Other loci/genes including Sr26, Sr24/Lr24 and Sr22 were tracked in none of the landraces tested. Data obtained from this study also showed that some wheat landraces were resistant to the 12 reported Pgt races TKTTF, TTTTF, PKTTF, TKSTF, PKSTF, PKTTC, PTRTF, PTTTF, PKSTC, TTRTF, TKSTC and PKRTF in seedling stage, while none of the studied loci/genes was detected in their genome. This might be an indication for presence of other identified or non-identified effective resistance genes within the genotypes. Based on the results of this study, wheat landraces carrying resistance genes could be used as sources of rust resistance in wheat breeding programs.