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本研究对２３个棉花黄萎病菌系，其中１９个为河北省棉区不同致病群（ＶＧｓ）的代表性菌系，用２５个可揭示菌系遗传多态性的随机引物进行ＲＡＰＤ扩增，研究了病菌的遗传分化及与其来源和致病性的关系。结果表明，菌系间的遗传相似系数变化在０．４４２～１．０００之间，但大多数菌系间的同源程度较高。基于８９个ＲＡＰＤ标记的聚类分析表明，供试菌系被划分为２个ＲＡＰＤ群（ＲＧｓ）和８个ＲＡＰＤ亚群（ＲＳＧｓ），其中河北省棉区黄萎病菌系的遗传分化程度较小，９５％的菌系归属于同一ＲＡＰＤ群（ＲＧ１），仅１个菌系属于ＲＧ２。ＲＡＰＤ类群与病菌地理来源有一定相关性，但与病菌致病群（ＶＧｓ）相关性不大。进一步分析表明，ＲＡＰＤ亚群（ＲＳＧｓ）与ＶＧｓ间存在一定关系，其中ＲＳＧ１中的８个菌系全部为强致病力的ＶＧⅠ菌系；ＲＳＧ２中６６．７％的菌系为ＶＧⅡ菌系。ＲＧｓ和ＲＳＧｓ与菌系是否与落叶型无关。
In this study, 23 cotton Verticillium dahliae isolates, of which 19 were representative strains of different pathogenic groups (VGs) in cotton area of Hebei Province, were amplified by RAPD using 25 random primers that could reveal the genetic polymorphism of the strain. , Studied the genetic differentiation of pathogens and its relationship with its origin and pathogenicity. The results showed that the genetic similarity coefficient between strains varied from 0.442 to 1.000, but most of the strains had higher homology. The cluster analysis based on 89 RAPD markers showed that the tested strains were divided into two RAPD groups (RGs) and eight RAPD subgroups (RSGs). Among them, the degree of genetic differentiation of Verticillium dahliae isolates in Hebei Province was smaller , 95% of the strains belonged to the same RAPD group (RG1), and only 1 strain belonged to RG2. The RAPD taxa are related to the geographical origin of the germs but not to the pathogenic germs (VGs). Further analysis showed that RAPD subpopulations (RSGs) had some relationship with VGs, of which 8 strains of RSG1 were all virulent VGⅠ strains and 66.7% of RSG2 strains were VGⅡ strains. Whether RGs and RSGs are related to the mycorrhiza has no relation with the deciduous foliage.