茄子棒孢叶斑病病原菌鉴定及致病性研究

Identification and pathogenicity of Corynespora cassiicola casuing Corynespora leaf spot on eggplant

本研究对茄子棒孢叶斑病的症状进行系统的描述,采用致病性试验、形态学观察及分子生物学的方法对茄子棒孢叶斑病的病原菌进行鉴定。致病性试验证实病原菌对茄子的致病力显著高于黄瓜。显微观察发现同一病原菌在茄子上形成的孢子以圆柱形为主,孢子体较窄;而在黄瓜上形成的孢子具有圆柱形和倒棍棒形两种形态,且较宽。对病原菌rDNA-ITS区进行PCR扩增和序列测定。综合形态特征、致病力和分子序列分析结果,确定茄子棒孢叶斑病病原菌为Corynespora cassiicola。

Corynespora leaf spot of eggplant was reported in China recent years. In this study, the damage and typical symptoms of this disease were reported. The pathogen caused Corynespore leaf spot was identified by pathogenicity testing, morphological characteristics and molecular identification. The pathogenicity of the isolates was significantly higher on eggplant than that on cucumber. The morphological identification showed that conidia of the pathogen were cylindrical and thin in shape, whereas were cylindrical or oblavate in shape on cucumber. The rDNA-ITS region of the pathogen was amplified by PCR and then sequenced. Based on the morphological characteristics, pathogenicity testing and rDNA molecular analysis, it was confirmed that the pathogen of Corynespora leaf spot in Shandong and Liaoning was Corynespora cassiicola .