Resistance to stripe rust in Turkish durum wheat varieties and wild emmer genotypes

Abstract

Stripe or yellow rust caused by Puccinia striiformis f. sp. tritici (Pst) is the most important disease of wheat causing significant yield losses. Growing resistant varieties is the most efficient and sustainable way to control this disease. The aim of this study was to investigate molecularly the presence or absence of the major resistance genes Yr5, Yr10 and Yr15 to stripe rust in 54 Turkish durum wheat (Triticum turgidum var. durum) varieties and 11 wild emmer (Triticum turgidum var. dicoccoides) genotypes. In addition, field trials were conducted during 2019-2020 under natural epidemic conditions in Antalya to determine phenotypic reactions of these genotypes against stripe rust. As a result of molecular analyses, none of the 54 durum wheat varieties had Yr5 resistance gene; however, the resistance genes Yr10 and Yr15 were determined in 12 and 17 varieties, respectively. Moreover, 7 of these varieties had both Yr10 and Yr15 genes. None of 11 wild emmer accessions had resistance genes examined. It was also determined that 28 varieties had resistant reaction to Pst race(s) under natural infection conditions whereas all wild emmer accessions were highly susceptible. This is the first study to identify major Yr-genes in Turkish durum wheat varieties and, therefore, these findings can be beneficial in wheat breeding programs to be conducted for resistance to stripe rust.