[Objective]The objective of this study is to explore the virulence evolution and relative relationship in main physiological races of Puccinia striiformis f.sp.tritici (Pst) in China, for searching the molecular evidence of somatic genetic recombination and revealing the virulence variation mechanism of physiological races of Pst in China.[Method]Virulence of 21 races collected during the past 12 years were tested on Chinese differentials, and then the genomic DNA isolated from them were used for SSR analysis by TP-M13-SSR technique.[Result]Twenty-one races were clustered into 4 groups in both virulent analysis and SSR markers, the correlation index between them is 0.21.Furthermore, 2 pairs of primers among 13 pairs showed the existence of recombinant among the physiological races.[Conclusion]The Chinese physiological races of Pst have abundant diversity of virulence, but the genetic divergence among them are low, the somatic recombination of urediospores acts as a possible major mechanism of virulence variation for Pst in China.%[目的]探索中国小麦条锈菌主要生理小种毒性演化关系及小种间的亲缘关系,以期寻找生理小种遗传重组的分子证据,进而揭示中国小麦条锈菌生理小种毒性变异机制.[方法]采用鉴别寄主分析毒性法和TP-M13-SSR荧光标记技术,对12年来收集的21个菌系进行毒性鉴定,并对其夏孢子基因组DNA进行SSR标记分析.[结果]毒性分析和SSR分析各将供试菌系聚为4个类群,两者的相关系数为r=0.21.另外,13对SSR引物中有2对引物显示条锈菌生理小种存在重组现象.[结论]中国条锈菌生理小种毒性多样性丰富,但遗传分化较低,条锈菌夏孢子阶段的体细胞遗传重组可能为毒性变异的主要方式之一.
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