宁夏葡萄霜霉病菌致病型鉴定及葡萄品种抗性评价

为合理利用葡萄抗性品种以及田间病害综合治理，采用离体叶盘接种法分别对2018年和2019年自宁夏回族自治区银川市、石嘴山市和吴忠市采集的43株葡萄霜霉病菌Plasmopara viticola菌株进行致病型鉴定及聚类分析，并对17个主栽葡萄品种进行抗性评价及聚类分析。结果表明：2018、2019年供试菌株致病力和供试葡萄品种抗性之间均存在显著差异，菌株平均病情指数与发病率呈显著正相关，皮尔逊相关系数r和回归系数R²分别介于0.45~0.96和0.20~0.92之间；2018、2019年供试菌株的强致病力菌株和弱致病力菌株分别为CS-YL和VI-BYDD、RG-JSJG和CS-YM；2018年和2019年供试菌株致病型被划分为强、中、弱3种类群，2年所占比例分别为10.00%、15.00%、75.00%和34.78%、39.13%、26.09%；供试17个葡萄品种的抗性类型可被划分为感病、抗病、高抗3种类群，2年所占比例均为17.65%、29.41%和52.94%。不同葡萄品种对不同菌株的抗性类型多样化。表明宁夏回族自治区葡萄霜霉病菌菌株致病力分化明显，不同菌株的致病型与其地域来源无关，不同葡萄品种的抗感程度不同。

Pathotype identification of downy mildew pathogen Plasmopara viticola and evaluation of variety resistance in Ningxia

For rational utilization of grape resistant varieties and comprehensive control of diseases in the field, the pathogenic types of 43 Plasmopare viticola strains from Yinchuan, Shizuishan and Wuzhong cities in Ningxia Hui Autonomous Region in 2018 and 2019 were identified and the resistance of 17 grape varieties was evaluated by using the method of in vitro leaf disk inoculation, and cluster analysis was carried out on the pathogenic types of the strains and the resistant types of grape varieties. The results showed that there were significant differences in the pathogenicity of the tested strains and resistance types among different grape varieties. The disease index and incidence rate were significantly positively correlated between the strains:Pearson''s correlation coefficient r and the regression coefficient R² were from 0.45 to 0.96, from 0.20 to 0.92, respectively. By calculating the weak pathogenicity rate, the strong and weak pathogenic strains of the tested strains in 2018 and 2019 were CS-YL and VIBYDD, RG-JSJG and CS-YM, respectively. Through cluster analysis, the pathogenic types of the tested strains were divided into strong, medium and weak types, with a proportion of 10.00%, 15.00%, 75.00% and 34.78%, 39.13%, 26.09%, in the two years, respectively. The resistance types of the tested grape varieties were divided into susceptible, resistant and highly resistant groups, with a proportion of 17.65%, 29.41%, 52.94%, in the two years, respectively. The resistance types of different grape varieties to different strains were diversified. There was an obvious pathogenicity differentiation in P. viticola in Ningxia, but the pathogenic types of the strains from different sources were not related to their geographical origins, as different varieties had different resistance and susceptibility responses.