番茄灰叶斑病原菌的鉴定及抗性种质资源的筛选

Identification of pathogen causing gray leaf spot on tomato and screening for resis-tant tomato germplasm

番茄灰叶斑病是一种世界性病害,近年来,该病在北京、台湾、海南、山东和浙江等地均有发生,极大地限制了我国番茄生产的竞争力[1]。该病害主要由Stemphylium spp.不同的4个种引起[2]。本研究采用形态观察法、ITS和gpd序列分析法对从番茄病株分离得到的病原菌进行鉴定,并对番茄灰叶斑病抗性鉴定方法进行研究,以期为番茄灰叶斑病的抗病育种研究及其利用提供理论依据。

Isolates of the gray leaf spot pathogen from diseased tomato plants were obtained by tissue-isolation method.Based on morphological characteristics,nucleotide sequences of ITS and gpd gene,the causal agents were identified as Stemphylium lycopersici.To screen available germplasm resources with gray leaf spot resistance,two inoculation methods,spray inoculation at the seedling stage and detached leaves identification method,were compared on two tomato materials 06-111 A and T11-024 A,and detached leaves identification method was selected to evaluate twenty-two tomato germplasm resources.The results indicated that eight germplasm were resistant,six were intermediate resistant and the others were susceptible.