大叶紫薇炭疽病病原的鉴定及生物学特性

Identification and biological characteristics of pathogens causing anthracnose of Lagetstroemia speciosa

为了明确大叶紫薇炭疽病的病原菌种类,为后续研究其发病规律及诊断防治提供理论依据,对海南出现的大叶紫薇炭疽病进行致病性测定、形态学鉴定和ITS、ACT、GAPDH、CHS序列分析,结果表明:引起海南大叶紫薇炭疽病的病原菌为隐秘刺盘孢(Colletotrichum aenigma)。生物学特性测定结果表明:大叶紫薇炭疽病原菌丝最适生长温度为30℃,最适pH为8。黑暗条件有利于其菌丝生长,在PDA、PSA培养基上的生长速率较快。

In order to clarify the pathogen species of anthracnose disease infecting Lagetstroemia speciosa to provide a theoretical basis for further study on its pathogenesis,diagnosis and control,the leaves of L.speciosa infected with anthracnose disease were sampled and isolated,and the isolates were determined in terms of pathogenicity and morphological characteristics and analyzed by using ITS,ACT,GAPDH and CHS sequence analysis.The isolates were identified as Colletotrichum aenigma,a pathogen causing anthracnose disease of L.speciosa.Biological characteristics tests showed that the pathogen had optimum mycelial growth when cultured at 30℃on the PDA medium with pH 8.Dark culture was conducive to mycelial growth of the pathogen,and the mycelia of the pathogen grew fast on both the PDA and PSA media.