湖南省草莓灰霉病菌遗传多样性研究

为探明湖南省草莓灰霉病菌群体遗传结构、分化及变异规律,采用荧光标记技术对湖南省9个地理菌群的180株草莓灰霉病菌基因组DNA进行SSR分析。结果表明:9对SSR引物共检测到56个观察等位基因(Na),平均值为6.22;有效等位基因(Ne)为1.27~4.89,平均值为3.44;不同位点的基因多样性指数(H)为0.21~0.80,平均值为0.65;不同位点Shannon’s信息指数(I)为0.37~1.83,平均值为1.34。供试180株样品9个SSR多态性位点上多态性信息量PIC变化范围为0.13~0.91,不同位点PIC差异大,这一规律与I和H基本一致。不同SSR位点总的遗传多样性(Ht)为0.21~0.77,平均值为0.65;群内遗传多样性(Hs)为0.19~0.50,平均值为0.40;遗传分化系数(Gst)为0.10~0.46,平均值为0.37;基因流(Nm)为0.58~4.47,平均值为1.16。不同地理菌群平均观察等位基因(Na)、有效等位基因数目(Ne)分别为2.93和2.07,Shannon’s信息指数(I)平均为0.67,基因多样性指数(H)平均为0.40,平均多态性位点数(NP)、多态位点百分率(P)分别为6.78和75%。依据不同地理菌群之间的遗传距离(0.2797~1.9225),将供试湖南省9个地理菌群分为4大类:第Ⅰ大类主要由长沙、邵阳、岳阳、衡阳、张家界、湘潭种群组成;第Ⅱ大类主要由郴州种群组成;第Ⅲ大类主要由株洲种群组成;第Ⅳ大类由常德种群组成。总之,湖南省各地草莓灰霉病菌群体遗传多样性丰富,但地理群体间差异小,病菌遗传变异主要来自群体内部,不同地区间存在病菌的移动。

Studies on Genetic Diversity of Strawberry Mould from Botrytis cinerea in Hunan Province

Abstract：In order to investigate the genetic structure of srawberry mould from Botrytis cinerea，its differentiation and veriation regulatory，this paper carried out SSR marker analysis on DNA of 180 srawberry mould from Botrytis cinerea genomes，collected from 9 locations of Hunan Province．The result indicated that a total of 56 alleles（Na）for 9 SSR loci were detected，the average value was 6.22．The effective number of alleles（Ne）ranged from 1.27-4.89，with an average value of 3.44．The Nei’s gene diversity（H）varied from 0.21-0.80，with an average value of 0.65．The Shannon’s information index（I）varied from 0.37-1.83，with an average value of 1.34．The polymorphism information content（PIC）for 9 loci ranged from 0.13-0.19，the variation law was generally coincident with the Shannon’s information（I）index and gene diversity index（H）．The denote gene diversity in the species（Ht）of different SSR loci ranged from 0.21-0.77，with an average value of 0.65．The gene diversity within populations（Hs）varied from 0.19-0.50，with an average value of 0.40．The population genetic differentiation（Gst）varied from 0.10-0.46，with an average value of 0.37．The gene flow （Nm）ranged from 0.58-4.47，with an average value of 1.16．At geographical population level，the observed number of alleles（Na）and the effective number of alleles（Ne）were 2.93 and 2.07，respectively．The average Shannon’s information index（I）and Nei’s gene diversity index（H）were 0.67 and 0.40，respectively．The number of polymorphic loci（NP）and the proportion of polymorphic loci（P）were 6.78 and 75%，respectively．Based on Nei’s genetic distance（ranging from 0.279 7-1.922 5），9 geographical populations of MLP isolates from different regions in Hunan Province were initially grouped into 4 clusters：cluster Ⅰ included isolates Changsha，Shaoyang，Yueyang，Hengyang，Zhangjiajie and Xiangtan，cluster Ⅱ included isolates Chenzhou，cluster Ⅲ included isolates Zhuzhou，and cluster Ⅳ comprised Changde．The genetic diversity of Botrytis cinerea population from Hunan Province is very rich，but there are small differences between different geographical population．The genetic variation in bacteria mainly comes from inside population，and Botrytis cinerea moves between different areas．