延边烟区烟草菌核病病原菌鉴定及抗性种质筛选

为防控延边烟区烟草菌核病提供基础资料和理论依据，开展了病原菌鉴定及抗性种质材料筛选研究。将收集的病原菌核采用常规方法进行分离、纯化，经致病性测定、形态学特征观察、rDNA-ITS测序比对及基于rDNA-ITS序列的系统发育分析，鉴定病原菌种类；并采用离体叶片法、活体叶片法对61份种质材料进行抗性筛选。结果表明：（1）经形态学、分子生物学方法鉴定该病原菌为核盘菌Sclerotinia sclerotiorum（Lib.）de Bary]。（2）两种方法筛选出31份高感材料、6份中感材料、15份抗病材料，鉴定结果一致率为85.25%，未筛选到免疫和高抗种质材料。延边烟区烟草菌核病病原菌为核盘菌，离体叶片法、活体叶片法可用于苗期烟草种质材料对菌核病抗性筛选。

Identification of Tobacco Sclerotinia Rot in Yanbian and Screening for Resistant Germplasms

Identification of pathogen and screening for resistant germplasm materials were conducted for providing fundamental data and theory for controlling tobacco sclerotinia rot in Yanbian tobacco areas.The sclerotium of pathogen were collected in 2015, and then isolated and purified by conventional methods.Pathogen was identified through pathogenicity test, morphological characteristics, sequence analysis of the internal transcribed spacer region of the ribosomal DNA (rDNA-ITS) and phylogenetic analysis based on rDNA-ITS sequences.61germplasm materials were screened by in vitro leaf-assay method and living leaf-assay method.The results showed that:(1) The pathogen was identified asSclerotinia sclerotiorum(Lib.) de Bary]by morphology and molecular biology methods.(2)31 high sensitive germplasms, 6 medium sensitive germplasms and 15 resistance ones were identified by the two methods with a consistent rate of 85.25%.No immune or high resistant germplasms, was identified.The pathogen of tobacco sclerotinia rot wasSclerotinia sclerotiorum(Lib.) de Bary]in Yanbian tobacco areas.In vitro leaf-assay and living leaf-assay methods can be used to screen the resistance of germplasm materials to sclerotinia rot at seedling stages of tobacco.