葡萄炭疽病菌鉴定及同源性分析

Identification and Homology Analysis of Colletotrichum gloeosporioides in Grape

为揭示葡萄炭疽病菌种类和遗传特征,给深入研究该病提供科学理论依据。本研究对不同地区的26株葡萄炭疽病菌通过形态学和r DNA-ITS序列分析进行鉴定及同源性研究。利用真菌通用引物ITS4、ITS5对病菌基因组进行PCR扩增,将测序结果与NCBI数据库上已知序列进行比对,同时利用Clustalx 1.83和MEGA 5.0软件进行聚类分析。结果表明:病菌菌落为白色或灰白色,菌丝呈绒状或絮状,分生孢子为圆柱形或圆筒状,单孢,无色;测得病菌ITS序列为500 bp左右,鉴定病原均为胶孢炭疽菌(Colletotrichum gloeosporioides)。不同地区葡萄炭疽菌的r DNA-ITS序列同源性高,亲缘关系比较近,但是各菌株间存在着遗传差异,并且菌株之间差异与地理来源和品种无明显的相关性。

The objectives are to clarify fungal species and genetic characteristics of Colletotrichum gloeosporioides, and provide basis for further studying this disease. The identification and homology analysis of26 strains of C. gloeosporioides from different districts were conducted by morphology and r DNA-ITS sequenceanalysis. PCR amplification was performed with fungal universal primers ITS4 and ITS5. We compared thesequences with the sequences available in NCBI, and cluster analysis was conducted with Clustalx 1.83 andMEGA 5.0 software. Results indicated that colony color was white or grey white, hypha exhibited velvet orflocculent, conidium showed cylindrical shape or cylindric shape, and was colorless; ITS sequence of pathogenwas about 500 bp, all identified pathogen were C. gloeosporioides. Although grape anthrax from differentdistricts exhibited high sequence homology and close genetic relationship, different strains showed geneticdifferences and this difference had no obvious correlation with geographical origin and varieties.