广西平果莲雾炭疽病病原菌鉴定

Identification of the causal agent causing waxapple anthracnose in Pingguo country, Guangxi

采用形态学特征观察和多基因系统进化分析进行病原种类鉴定。结果表明:病原菌在PSA培养基上初生菌丝为白色,逐渐转变成墨绿色至灰黑色,孢子堆为橘红色,分生孢子为单细胞,无色透明,长椭圆形,8.5~17.5μm×3.5~4.5μm,有的含有1~2个油球,萌发产生附着胞;病原菌的ITS序列与果生刺盘孢菌(Colletotrichum fructicola)相似性最高,达99.7%;基于ACT、ITS、CHS-1、GPDH和TUB2基因序列构建的多基因联合系统进化结果显示,病原菌与果生刺盘孢菌的不同分离物聚集在同一个分支上,结合其形态学特征将病原菌鉴定为果生刺盘孢菌。

The morphologies of colony and conidia, and phylogenetic analysis of multiple genes were performed to identify the pathogen causing waxapple anthracnose. The results showed that colony of the isolated pathogen on the potato sucrose agarose （PSA） was white, later becoming atrovirens and reverse gray black, and the Conidial masses were orange. Conidia was one-celled, colorless transparent, long elliptic, 8.5-17.5 μm × 3.5-4.5 μm, and contains 1-2 oil-ball with appressorium when germinating. Sequence analysis of the internal transcribed spaces（ITS） revealed that the isolates pathogen was highly similar to Colletotrichum fructicola （99.7% nucleotide identity）. Phylogenetic analysis, which based on ITS, β-tubulin, chitin synthase A, actin, and glyceraldehydes-3-phosphate dehydrogenase sequences, showed that the pathogen was clustered with the C.fructicola.According to its characteristics of morphology and phylogenetic analysis of multiple genes, the pathogen of waxapple anthracnose was identified as C.fructicola.