Sárgarozsda rezisztenciagének azonosítása szegedi és külföldi búzafajtákban molekuláris markerek segítségével

Abstract

Yellow rust (Puccinia striiformis f. sp. tritici) is one of the most important diseases of wheat. Although this disease was rare in Hungary, heavy epidemics occurred here in the last three successive years. In the year of 2014, we observed 70% yield loss in the most susceptible cultivars. To effectively use yellow rust resistance genes (Yr), it is important for breeders to know the resistant genotypes in current cultivars. In this study some winter wheat cultivars (mainly in Central Europe) were investigated using molecular markers to determine the presence and absence of three important Yr genes (Yr9, Yr17 and Yr18). Among the cultivars three carried yellow rust resistance gene Yr9, four had Yr17, and Yr18 was found in five cultivars. Severity of the natural infection changed from 0% to 90% during 2014. Field scoring data demonstrated the Yr9 to be ineffective, while Yr18 provided some protection. Among entries 11 proved to be resistant, and all four cultivars carrying Yr17 belonged to this group. Therefore, the rest of resistant cultivars might have other effective Yr genes. As more than fifty percent of cultivars investigated proved to be susceptible to yellow rust there is a need to introduce new, effective Yr genes into new wheat cultivars. The use of molecular markers is a convenient approach to identify effective yellow rust resistance genes in cultivars, and marker assisted selection can be efficiently applied to develop resistant wheat cultivars.