Potato Verticillium Wilt Pathogens Isolation,Identification And Diversity Analysis In Northeast And North China And Biocontrol Of This Disease

Potato Verticillium wilt is one of the main diseases influence the potato yield and quality.In order to understand the spread of Potato Verticillium wilt and make sure the pathogen species,we collected potato disease samples from Shanxi,Hebei,Heilongjiang province,and some regions of Inner Mongolia from 2013 to 2015.We got 132 strains totally by tissue isolation method.Based on strain colony,ITS and specific primers identification,the results showed two species of strains,one is Verticillium dahliae from 72 strains,another is V.albo-atrum from 60 strains.We used ISSR method to analysis genetic diversity of the two species and want to make sure the relation of genetic relationship,geographical distribution and virulence.Results showed that the genetic distance from Wulanchabu strains was far from that strans from Xilinguole,northeast China,and Hebei areas;Genetic diversity analysis of different pathogenic strains showed that the two pathogens were consistent with each other,there was no significant genetic difference between the strong pathogenic strains and the medium pathogenic strains,but there were significant differences between the weak pathogenic strains and the medium pathogenic strains,and strong pathogenic strains.The strain XT1-4 showed obvious control effect on potato Verticillium wilt,and the control rate was more than 60%.It was identified as Bacillus tequilensis by morphology and gram straining method and could be used as a potential biocontrol agent on prevention and treatment of potato verticillium wilt.