栗疫病菌的致病力分化

采用树皮下接种和打孔接种的方法,在板栗树苗和离体栗枝上测定了栗疫病菌的致病力。结果表明,两种接种方法测定病菌致病力比较一致;据此可将菌株分为强致病力和低致病力两类。对低致病力菌株分生孢子后代的不同培养型也进行了致病力测定,野生型单孢菌株的毒力明显比亲本型单孢菌株的强。讨论了低致病力菌株的毒力降低的原因。

Differentiation of Virulence of Cryphonectria parasitica,the Pathogen of Chestnut Blight

Pathogenicity of isolates of Cryphonectria parasitica,the pathogen of chestnut blight,was evaluated by subcortexinoculating small Chinese chestnut samplings and boreinoculatingisolated chestnut branches.Data showed that there was no obvious difference between the re-sults of inoculation using two methods.On these grounds,isolates could be divided into twotypes of virulence and hypovirulence.In addition,we tested virulence of isolates,single conidiospore cultures of hypovirulent strains,with different culture characteristics.Results indi-cated that virulence of single spore cultures with wild type characters was higher obviouslythan that with parental type characters.The cause of the decline of the virulence of isolateswas discussed.