西南桦苗木猝倒病的症状及其病原菌的鉴定  

Identification of Damping-off Pathogen on Betula alnoides

作　　者：李娅[1] 武自强[2] 景跃波[1] 庞静[1] 赵永红[1] 李翠萍 曾郁珉 伍建榕[2] 

机构地区：[1]云南省林业科学院,云南昆明650201 [2]西南林业大学林学院,云南省高校森林灾害预警控制重点实验室,云南昆明650224 [3]云南省林业技术推广总站,云南昆明650224

出　　处：《西部林业科学》2013年第1期86-90,共5页Journal of West China Forestry Science

基　　金：国家林业局948项目:“热区主要造林树种无土育苗技术引进”(编号2011-4062);“云南省重点学科森林保护学”(XKZ200905);云南省高等学校森林病虫害综合治理教学团队

摘　　要：从西南桦幼苗猝倒病的病苗中分离获得频率最高的猝倒病病原菌,通过病原菌的形态特征、培养性状和致病性测定的方法对引起西南桦幼苗猝倒病的病原菌进行了分离鉴定,采用PCR技术扩增病菌rDNA-ITS基因,获得一长度为560～634 bp的DNA片段,序列测定结果表明,该片段序列与尖孢镰刀菌和腐皮镰刀菌序列的同源性均达到了99%;致病性试验结果表明,该菌具有较强的致病性,发病率高达100%。综合两种方法鉴定结果,尖孢镰刀菌和腐皮镰刀菌是该地区西南桦苗木猝倒病的致病菌。The pathogenic fungi causing damping-off of Betula alnoides in Puwen experimental forest farm at Xishuangbanna of Yunnan province, were isolated and identified. The morphological and culture characteristics of the pathogens were studied, and the pathogenicity of pathogens were tested as well. By using polymerase chain re-action （PCR） technique to amplify rDNA - ITS of the isolate, we obtained a 560 - 634 bp DNA fragment, the se- quencing result and NCBI blast showed that the rDNA-ITS sequences of the isolate shared 99 % homology with Fusarium oxysporum and Fusarium solani. Combining the identification of both morphological method, molecular method, and the pathogenicity test of 100 % disease incidence, it was concluded that F. oxysporum and F. solani were two pathogens causing damping-off disease of B. alnoides seedling.

关 键 词：西南桦 苗木猝倒病 病原菌 rDNA—ITS测序 

分 类 号：S763[农业科学—森林保护学]