一种银耳段木栽培杂菌的形态学鉴定与分子生物学分析  

Morphologic identification and molecular analysis on a contaminative fungus from wooden cultures of Tremella fuciformis

作　　者：张春雷[1,2] 彭卫红[1,2] 温文婷[1,2] 郭勇[2] 周洁[2,3] 梁勤[2,3] 杨志荣[1] 

机构地区：[1]四川大学生命科学学院,成都610064 [2]四川省农业科学院土壤肥料研究所,成都610066 [3]四川农业大学资源环境学院,雅安625014

出　　处：《菌物学报》2010年第1期96-105,共10页Mycosystema

基　　金：四川富民强县专项"银耳优良新品种选育"资助项目

摘　　要：从四个不同银耳段木栽培场地采集杂菌样本,经初步鉴定后纯化得到48个菌株。通过对子实体、孢子及菌丝等的形态观察确认从银耳栽培段木上分离的48株杂菌隶属于炭团菌属,在形态上与截头炭团菌Annulohypoxylon annulatum最为相似。为了进一步确认从银耳栽培段木上分离的48株杂菌的分类地位,对其中14个供试菌株进行了ITS系统发育分析,结果表明:14个供试菌株之间的遗传距离为0.036时可以形成两个明显分枝,且分枝与地理来源之间并无明显相关性;供试菌株在分类地位上属于炭团菌属,与形态学鉴定结果一致,并与截头炭团菌的关系最为接近,遗传距离在0.2左右;与银耳伴生菌香灰菌的遗传距离为0.29左右。从75条引物中筛选出13条引物对所有48个供试菌株进行ISSR扩增,扩增共获得103条带,其中多态性条带72条,占条带总数的69.9%。聚类分析结果表明:在相似水平为75%时,48个菌株可以划分为5个类群,且类群的划分与地理来源之间并无明显相关性;多数供试菌株之间的遗传相似性较低,这表明供试菌株在DNA水平上存在比较显著的遗传变异,具有较丰富的遗传多样性。48 contaminative flmgal isolates were obtained from wooden cultures of Tremella fuciformis which were collected from four different geographic origins. Morphologic identification showed that the 48 tested strains belonged to Annulohypoxylon and bore a resemblance to Annulohypoxylon annulatum. To affirm the taxonomic position of these isolates more precisely, ITS sequences of 14 tested strains were sequenced, and then subjected to phylogenetic analysis. The result showed that the resultant phylogenetic tree of the 14 tested strains consisted of two clades, was separated in the genetic distance of 0.036 and there was no obvious correlation between geographical distribution and genetic distance. The tested strains were confirmed as Annulohypoxylon, consistent with the morphologic identification. The genetic distance between the tested strains and Annulohypoxylon annulatum was around 0.2; whereas the genetic distance between the tested strains and an unknown cohabitant fungus of Tremellafuciformis was around 0.29. 75 ISSR primers were screened and 13 of them were selected to amplify the 48 tested strains and a total of 103 fragments were amplified, among them 72 （accounting for 69.9% of the total） were polymorphic. These 48 tested strains were divided into 5 groups under similarity of 75%, with no obvious correlation between geographical distribution and groups, by cluster analysis. The results showed that genetic similarity of these tested strains was low and there were obvious genetic variations in DNA level.

关 键 词：截头炭团菌 香灰菌 遗传多样性 

分 类 号：S435.673[农业科学—农业昆虫与害虫防治]