滇重楼稻曲拟盘多毛孢叶斑病病原鉴定及其生物学特性测定

Pathogen identification and biological characteristics of Paris polyphylla var.yunnanensis leaf spot disease caused by Pestalotiopsis oryzae

为明确滇重楼Paris polyphylla var.yunnanensis(Franch)Hand.-Mazz一种新的叶斑病病原菌,以云南省丽江市玉龙纳西族自治县中药材种植基地内发现的一种新真菌性病害为供试研究材料,经单孢分离培养、形态特征观察、致病性测定、多基因系统发育分析(ITS、tub 2、tef 1)和生物学特性测定,对病原物进行分类鉴定。研究结果表明,病原物CL107形态符合Pestalotiopsis sp.种属典型特征;菌株CL107-ITS(accession no.MK156295)、CL107-BT(accession no.MN015425)、CL107-EF1(accession no.MN022941)与参比标准菌株P.oryzae CBS 353.69同源性分别为100.00%、100.00%、98.92%,可将稻曲拟盘多毛孢P.oryzae确定为滇重楼叶斑病病原物。生物学特性研究表明,PDA培养基、pH 8.0、28℃、全黑暗条件有利于菌株CL107菌丝生长和分生孢子形成,以葡萄糖为碳源有利于纯化菌株菌丝生长和产孢;以酵母提取物为氮源有利于纯化菌株菌丝生长,以牛肉膏为氮源有利于纯化菌株产孢。本研究首次报道稻曲拟盘多毛孢P.oryzae可侵染滇重楼植株,引起真菌性叶斑病,明确影响病害发生的环境因子,为该叶斑病的诊断与防治提供科学依据和理论指导。

In order to characterize a new fungal leaf spot disease of Paris polyphylla var.yunnanensis(Franch)Hand.-Mazz,the fungal pathogens were isolated in a Chinese herbal medicine planting base in Yulong Naxi autonomous county,Lijiang,Yunnan.The pathogens were classified and identified based on single spore isolation culture,morphological observation,pathogenicity assay,multi-gene phylogenetic analysis(ITS,tub 2,tef 1)and biological characteristics.The results showed that the pathogen morphology of CL107 was consistent with the typical characteristics of Pestalotiopsis sp.;strains CL107-ITS(accession no.MK156295),CL107-BT(accession no.MN015425),CL107-EF1(accession no.MN022941)and the reference standard strain P.oryzae CBS 353.69 shared a high homology of 100.00%,100.00%and 98.92%,respectively.P.oryzae was the leaf spot disease pathogen of P.polyphylla var.yunnanensis.The biological characteristics of the strain CL107 was beneficial to mycelial growth and conidial formation in PDA medium at pH 8.0,28℃,and under all dark conditions.The use of glucose as the C source was beneficial to the growth and sporulation of the purified strains.The yeast extract was used as the N source,which was beneficial to the mycelium growth of the purified strain,and the beef extract used as the N source could facilitate the sporulation of the purified strain.This study firstly reported that P.oryzae could infect P.polyphylla var.yunnanensis,which caused fungal leaf spot.The environmental factors affecting the occurrence of the disease were also identified,which would provide a scientific basis and theoretical support for the prevention and control of the leaf spot disease.