In China, Xinjiang is a relatively independent epidemic region of wheat stripe rust, caused by Pucciniastriiformisf. sp. tritici, due to great population genetic divergence of Xinjiang with other inland epidemic regions. In this region, race evolution was usually slower than inland populations. However, many new races have recently been found, and therefore, it is necessary for more understanding of the virulence evolution of the Xinjiang population. So, in this study, a 65 sexual progenies, derived from a Xinjiang single-urediospore isolate BGTB-1 of P.striiformisf. sp. triticiby selfing on alternate host barberry (Berberisaggregata). It was phenotyped on the 25 single Yrlines, and genotyped by 19 kompetitive allele-specific PCR-single nucleotide polymorphism (KASP-SNP) markers. As a result, the 65 progenies were identified as 56 various virulence patterns (VPs), and neither of which was identical to the parental isolate, showed 100% virulence variation. Compared with the parental isolate, of all progenies, 39 (60.0%) had increased virulence, and 18 (27.7%) had decreased virulence. All progenies exhibited avirulence to Yr10, Yr15, Yr32, and YrTr1loci, and avirulence and virulence segregation at the remaining 21 Yrresistance loci. The results showed avirulence to Yr5, Yr7, and Yr76(A:V≈3:1) loci is controlled by a single dominant gene, and that to Yr6, Yr25, and Yr44(A:V≈1:3) loci by a single recessive gene. However, avirulence to the remaining 15 resistant loci including Yr1, Yr2, Yr3, Yr4, Yr8, Yr9, Yr17, Yr26(=Yr24), Yr28, Yr29, Yr43, YrSP, Yr27, YrA, and YrExp2, with various avirulence and virulence segregation ratios, is controlled by two genes with different gene effects, indicating complex genetic traits of the parental isolate. Totally, 65 dissimilar genotypes detected among progenies using overall molecular markers, by which a linkage map was constructed, with a genetic distance of 441.0 cM. Interestingly, although the parental isolate was avirulent to Yr5, but 17 progenies showed virulence, showing the change of pathogenicity from avirulence to virulence at this resistance locus. It was for the first time to report that progenies with virulence to Yr5produced sexually from avirulent parental isolate at this resistance locus. To our knowledge, this study offers an insight into inheritance, sexual reproduction and virulence variation of P.striiformisf. sp. triticiin Xinjiang, facilitating us to understand evolution of the rust pathogen in this region and accounting for Xinjiang population distinguished form other inland populations. Additionally, it is necessary to further confirm the roles of sexual reproduction in the emergence of new races and affecting population genetic diversity of P.striiformisf. sp. triticiunder natural conditions in Xinjiang.

wax gourd  /  SNPs genotyping array  /  heterosis  /  cultivar identification  /  DNA fingerprint