吉林省烟草野火病菌群体分子多态性分析

Analysis of Molecular Polymorphism of Pseudomonas syringae pv.tabaci in Jilin Province

为研究烟草野火病菌的群体遗传多样性，采用正交试验方法，对5个多态性引物（ REP，ERIC，BOX， J3，IS1112）的Rep－PCR反应体系分别进行了优化，同时优化了体系中的Mg2＋、dNTP、rTaq 酶等几个因素，并在此基础上对来源于吉林省不同地区的70株烟草野火病菌进行了分子多态性分析。结果表明：优化的PCR反应体系电泳图谱清晰，多态性丰富，重复性好，适合烟草野火病菌群体分子标记研究。通过聚类分析发现，吉林省烟草野火病菌群体存在分子多态性，在遗传相似系数为0？9时，70个菌株被聚为4个类群（ G1～G4），其中G1类群最大（39个菌株，占55？71％），而G3类群最小，仅包括2个菌株。 G1和G2类群分别包含了5个和3个亚群。不同类群和亚群的菌株地理来源存在多样性。

To study the population genetic diversity of Pseudomonas syringae pv. tabaci, the orthogo？nal design of L9（34）was used to optimize PCR reaction system factors including Mg2＋,dNTP,rTaq DNA polymerase and primers of five polymorphic primers（REP,ERIC,BOX,J3 and IS1112）. Mo？lecular polymorphism of 70 strains isolated from different areas in Jilin province was analyzed using the optimized Rep-PCR system. The results showed clear electrophoresis, high polymorphism and stable repeatability with the optimized Rep-PCR system which was suitable for study of molecular polymorphism of P. syringae pv. tabaci. The clustering results revealed that molecular polymorphism existed in the population of P. syringae pv. tabaci from Jilin province. The tested 70 strains were clustered into four groups （ G1—G4） with 0？9 of genetic similarity coefficient, in which G1 group was the most （ 39 strains,55？71%） , while G3 group was the least （ only 2 strains） . The groups G1 and G2 were separated into five and three subgroups, respectively. For geographical origin of strains in different groups and subgroups, diversity exists.