陇南地区小麦条锈菌群体遗传多样性SSR分析

SSR Analysis of Population Genetic Diversity of Puccinia striiformis f.sp.tritici in Longnan Region of Gansu,China

【目的】甘肃陇南地区是小麦条锈菌最主要和最大的越夏区,本研究的目的是分析该地区的小麦条锈菌自然群体的遗传结构,探索其分子遗传变异规律。【方法】采用TP-M13-SSR荧光标记技术,对甘肃省陇南地区8个种群409个小麦条锈菌分离株基因组DNA进行SSR标记分析。【结果】陇南地区小麦条锈菌的观察等位基因数(Na)为1.95,有效等位基因数目(Ne)为1.43,Nei's(1973)基因多样性指数(H)为0.27,Shannon信息指数(I)为0.41。武都、文县和秦城种群遗传多样性较高,徽县、成县和西和种群相对较低。AMOVA分析结果表明,小麦条锈菌群体间和群体内都存在着一定的遗传分化,群体间的遗传变异占总变异的12.5%,群体内遗传变异占87.5%。地区间的基因流Nm=1.83。【结论】陇南地区小麦条锈菌群体遗传多样性很丰富,但地区之间有一定的差异;群体遗传变异主要存在于群体内部,不同地区间存在基因的交流和病原菌的移动。

[Objective] As Longnan region of Gansu province is one of the largest and most important over-summering areas of Puccinia striiformis f. sp. tritici in China, the objective of this study is to determine the genetic structure of P. striiformis f. sp. tritici populations in this region. [ Method] Population genetic diversity of the P. striiformis f.sp. tritici population containing 409 isolates collected from 8 different areas in Longnan, Gansu province was investigated with TP-M 13-SSR technique. [Result] For the Longnan population, the average number of alleles （Na） per locus was 1.95, and the effective number of alleles （Ne） was 1.43. The Nei＇s gene diversity （H） and Shannon＇s information index （I） were 0.27 and 0.41, respectively. The genetic diversity of Wudu, Wenxian and Qingcheng populations was much higher than that of Huixian, Chengxian and Xihe populations. Analysis of AMOVA showed that there were about 12.5% of the total variations among the collections, 87.5% of the total variation presented within collections. Gen flow （Nm） was 1.83. [Conclusion] The important conclusion is that the populations ofP. striifornis f. sp. tritici possessed relatively high levels of genetic diversity but a lower genetic differentiation in Longnan of Gansu. The main genetic variation presented within collections. There is an extensive gene flow and migration of pathogen among the regions in Longnan of Gansu.