Virulence analysis of wheat stem rust pathogen (Puccinia graminis f. sp. tritici) using differential lines
Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
Wheat stem rust caused by a fungus Puccinia graminis f.sp tritici (Pgt) is one of the most significant wheat diseases infecting all the above-ground parts of the wheat plant. Pgt is an obligate biotrophic pathogen with rapid genetic changes through sexual reproduction on alternative host barberry and spontaneous mutations during its life cycle. Emergence and prevalence of new races result in incidence of epidemies on susceptible wheat. To monitor the genetic change and virulence variability of Pgt population, we studied the collected wheat stem rust samples from eight different provinces of Iran during 2020–2022. For each sample, virulence was assessed on the seedling stage of 20 North American differential lines carrying one of stem rust resistance genes Sr5, Sr21, Sr9e, Sr7b, Sr6, Sr8a, Sr9b, Sr9a, Sr9g, Sr11, Sr36, Sr30, SrMcN, Sr31، Sr24, Sr17, Sr9d, Sr10, SrTmp and Sr38 . Results showed that among purely thrived 43 samples, the most virulence was on lines carrying Sr5, Sr6, Sr8a, Sr9b, Sr30, Sr17, Sr21, Sr9e, Sr7b, Sr9d, Sr10, SrTmp, Sr38 , and SrMcN , while lines carrying Sr31 and Sr24 genes were resistant to the most of races. Data revealed that the majority of isolates belong to virulent races TTTTK, TTTTF, PTTTK and TKTTK. Races PTTTK and TTTTF were the most frequenct among all 13 identified races. To our knowledge, races TTTTK and PTTTK have not been reported previously from Iran. To employ the effective genes in wheat breeding programs, continuous monitoring of genetic change and virulence variability of Pgt population is required.
