Identification of New Sources of Resistance to Septoria Tritici Blotch Caused by Zymoseptoria tritici

Abstract

Twenty‐nine synthetic hexaploid wheats (SHWs) were evaluated for resistance to five isolates of Zymoseptoria tritici, a devastating wheat pathogen worldwide. The five Z. tritici isolates varied in their virulence spectra towards wheat genotypes, indicating that they have distinct set of avirulence genes. New isolate‐specific resistances were identified that could be used in wheat breeding programmes. Comparing with the previous studies, the number of specific resistances identified in this study is considerable. Among 150 interactions, 78 isolate‐specific resistances were identified. Interestingly, 21 wheat genotypes showed specific responses to one or more isolates tested. Of these, 12 genotypes were highly resistant to all isolates, indicating that they possess known or novel effective resistance genes. The Stb15 and Stb16/Stb17 are effective resistance genes towards isolates used in this study, indicating that the conferred resistance in these genotypes is due to the presence of either of these genes in combination or individually. Alternatively, they may carry novel broad‐spectrum resistance gene(s) that their identification is of interest. Our data suggest that the presence of complete resistance to various Z. tritici isolates in SHWs justifies the need for more in‐depth research to characterize the likely novel genes.

Whole-genome diversity, population structure and linkage disequilibrium analysis of globally diverse wheat genotypes using genotyping-by-sequencing DArTseq platform

“…Despite extensive wheat breeding programs worldwide as well as in Iran, it appears most of the modern high-yielding wheat cultivars are vulnerable to environmental stresses. Therefore, continuous screening and characterization of wheat genotypes possessing favorable genes is required to integrate these new sources into breeding gene pool (Mehrabi et al 2015;Alipour et al 2017;Fayaz et al 2019). Recently, Diversity Arrays Technology provided a DArTseq platform as robust molecular markers (SilicoDArT and SNP) for genetic diversity and genome mapping in many crops (Pailles et al 2017;Mogga et al 2018;Ndjiodjop et al 2017;Alam et al 2018) as well as in wheat (Monostori et al 2017;Ovenden et al 2017;Baloch et al 2017).…”

Genetic analysis of novel resistance sources and genome-wide association mapping identified novel QTLs for resistance to Zymoseptoria tritici, the causal agent of septoria tritici blotch in wheat

“…In addition, the application of fungicides has severe threats to human health and the environment. Therefore, the characterization of new resistance sources and the development of resistant wheat cultivars is the most economical and environmentally-friendly approach and fundamental strategy in breeding programs for sustainable agriculture and food security (Talebi et al 2010;Mehrabi et al 2015). Up to now, 22 major genes and 89 QTLs for resistance to Z. tritici have been reported and mapped on the wheat genome along with their closely linked markers (reviewed by Brown et al 2015; Yang et al 2018).…”

Genome-wide association mapping in wheat reveals novel QTLs and potential candidate genes involved in resistance to septoria tritici blotch

“…Novel sources for resistance to Z. tritici Zymoseptoria tritici is one of the most important foliar diseases in many wheat-growing areas, including Europe, Northern America and Asia (Hardwick et al 2001;Mehrabi et al 2015). The use of genetic resistance is the most appropriate strategy to control the disease.…”