2015年湖北省小麦条锈菌群体结构及多样性分析

Population Structure and Diversity Analysis of Puccinia striiformis f.sp.tritici in Hubei Province in 2015

为了明确湖北省小麦条锈菌生理小种的构成以及变化动态,利用中国鉴别寄主对2015年采自湖北省6个地(市)的102份条锈病标样进行了群体结构分析,鉴定到已知条锈菌小种(类型)19个,其中CYR33和CYR32是湖北省的优势小种,出现频率分别居第一位(40.2%)和第二位(17.65%),其他小种(类型)以水源11类群、Hybrid 46类群以及贵农22类群为主,首次从湖北省标样中监测到贵农22菌系,其出现频率为17.64%。群体多样性研究结果表明,被测条锈病标样在物种水平上的Nei’s基因多样性指数(H)为0.19,Shannon’s信息指数(I)为0.31,表明湖北省小麦条锈菌毒性多样性比较丰富。UPGMA聚类分析结果表明,湖北省小麦条锈菌群体毒性遗传相似系数范围为0.95~0.99,相似系数较高,遗传距离较小,群体之间交流广泛,并且毒性遗传结构与地理距离无相关性。

In order to clarify races composition and dynamics of Puccinia striiformi sf. sp. tritici （ Pst ） in Hubei province, 102 wheat stripe rust samples collected from six cities in Hubei province in 2015 were identified on Chinese differential hosts. Nineteen Pst races were detected. Among these races, CYR33 and CYR32 were the most prevalent races in Hubei province, ranking the first（40. 2 % ） and second（17. 65 %）, respectively. The other Pst races mainly belonged to Suwon 11 group, Hybrid 46 group and Guinong 22 group. In addition,Guinong 22 group was firstly detected in Hubei province,and its occurrence frequency was up to 17. 64%. The group diversity study showed that Nei＇s genetic di-versity index（H） and Shannon＇s information index（J ） were 0. 19 and 0. 31 at the species level,respec-tively, indicating that the toxicity diversity of Pst races in Hubei province is high. UPGMA cluster a-nalysis indicated that the similarity coefficient of genetic toxicity of Pst population ranges from 0. 95 to 0. 99,which suggested high similarity coefficient, short genetic distance and extensive communication among different groups,and there is no correlation between the toxicity genetic structure of tripe rust population and the geographical distance.