四川省丁香假单胞猕猴桃致病变种的遗传多样性分析

Genetic Diversity of Pseudomonas syringae pv. actinidiae strains in Sichuan

为明确四川省猕猴桃溃疡病菌丁香假单胞菌猕猴桃致病变种(Pseudomonas syringae pv.actinidiae,Psa)的遗传多样性及群组划分与地理来源的相关性。以四川省不同地理来源的40个Psa菌株为研究试材,用rep-PCR技术进行分子标记,NTSYS软件分析UPGMA聚类。3对rep-PCR检测引物(REP、ERIC和BOX)共获得42个位点,其中38个为多态位点,占90.5%。UPGMA聚类结果显示,以相似系数为0.70阀值时,40个Psa菌株被分为2个类群(Ⅰ、Ⅱ),其中85.0%的菌株属于第Ⅱ类群;在相似性系数为0.80时,第Ⅰ类又可分为2个亚类(Ⅰ-1、Ⅰ-2),第Ⅱ类则分为5个亚类(Ⅱ-1、Ⅱ-2、Ⅱ-3、Ⅱ-4、Ⅱ-5),菌株无明显的采集地聚类。以上结果表明,四川省各地区的猕猴桃溃疡病菌菌株具有较高的遗传多样性,但其遗传变异与菌株地理来源无明显相关性。

To determine the genetic diversity of kiwifruit ulcer pathogen Pseudomonas syringae pv.actinidiae(Psa)in Sichuan and the correlation between genetic group division and geographical origin,40 Psa strains from different regions of Sichuan were used as the research materials,rep-PCR was used for molecular marker,and UPGMA clustering was conducted with NTSYS software.A total of 42 loci were obtained by 3 primer combinations(REP,ERIC and BOX),including 38 polymorphic loci,the rate of polymorphism was 90.5%.The results of UPMGA cluster analysis indicated that 40 Psa strains were divided into two groups(Ⅰ,Ⅱ)in the genetic similarity coefficient of 0.70,and 85.0%of the strains belonged to theⅡgroup.The groupⅠcontained two sub-groups(I-1,I-2)and the groupⅡconsisted of five sub-groups(Ⅱ-1,Ⅱ-2,Ⅱ-3,Ⅱ-4,Ⅱ-5)in the genetic similarity coefficient of 0.80,but all strains had no obvious clustering of collecting locations.This study showed a rich polymorphism of Psa strains from different regions of Sichuan,but the genetic diversity had no significant correlation with geographical location.