基于RAPD标记分析葡萄孢属类似真菌Amphobotrys ricini的遗传多样性
RAPD based analysis of genetic diversity of Botrytis-like fungus Amphobotrys ricini

采用RAPD分子标记对我国15个地区2种寄主植物（铁苋菜和蓖麻）上分离得到的葡萄孢属类似真菌Amphobotrys ricini的81个菌株以及来自美国的1个A. ricini菌株进行了遗传多样性分析。结果显示：筛选出的8条RAPD引物共扩增出63条DNA带，其中有49条DNA条带为多态性条带，多态性条带比率（PPB）为77.8%。多态性信息含量 （PIC）值变化范围在0.47～0.84，平均值为0.72，观测等位基因数（Na）的均值为2.000 0、有效等位基因数（Ne）的均值为1.357 7、Nei’s基因多样性指数（H）的均值为0.227 5，Shannon信息指数（I）的均值为0.363 1。UPGMA聚类分析表明，遗传相似系数变化范围在0.55～1.00，以遗传相似系数0.70为阈值时，可分为5个类群（A、B、C、D、E），在遗传相似系数0.74处，B类群又可以分为B1和B2两个亚群。分析结果表明，A. ricini 群体内遗传变异与菌株地理来源、寄主植物有一定相关。
In this study,genetic diversity among 82 Amphobotrys ricinistrains (81 strains from castor bean Ricinus communis L. and copperleaf Acalypha australis in China,1 strain from USA) was studied based on RAPD technology. The results showed that eight RAPD primers produced 63 DNA bands in total,of which 49 DNA bands were polymorphic DNA bands with the percentage of polymorphic DNA bands (PPB) reaching up to 77.8%. Polymorphism information content (PIC) values ranged from 0.47 to 0.84 with a mean value of 0.72. The number of observation alleles (Na) was 2.000 0,the number of effective alleles (Ne) was 1.357 7,Nei’s genetic diversity index (H) was 0.227 5 and Shannon information index (I) was 0.363 1. UPGMA cluster analysis showed that genetic similarity (GS) ranged from 0.55 to 1.00 among the 82 investigated A. ricini strains. Samples could be divided into 5 groups (A,B,C,D,E) at the GS of 0.70 and B group could be divided into B1 and B2 subgroups at the GS of 0.74. The RAPD groups had a certain correlation with the geographical origin and the host of the strains. In summary,the study revealed the genetic diversity of the A. ricini population and its relationship with geographical origin and host.