草业学报2016，Vol.25Issue(3)：32-42,11.DOI:10.11686/cyxb2015214
青藏高原高寒草地优势禾草－紫花针茅内生真菌分离和鉴定
Isolation and identification of endophytes infecting Stipa purpurea,a dominant grass in meadows of the Qinghai-Tibet Plateau
摘要
Abstract
Stipa purpurea is a dominant grass species in alpine grassland of the Qinghai - Tibet Plateau. Research on this species to date has focused on defining genetic diversity,community classification,ecological function,physiological traits and grassland community characteristics;however,isolation and identification of endophyte fungi from S .purpurea has seldom been attempted.Endophyte was isolated from S .purpurea by leaf surface sterilization and axenic culture,and hyphae,colony physical characteristics,and conidial morpholo-gy were observed.Endophyte nucleotide sequences were cloned by tubB ,tefA,and actG specific primers,and representative endophyte sequences were downloaded from Genbank to determine homology.A maximum like-lihood method was applied to construct a phylogenetic tree.It was found that endophyte occurrence in S .pur-purea was relatively high in Qinghai province,compared to other sites.Colony morphology characteristics, growth speed and morphology of conidia were identical to those of Epichloёspp.The results of tubB and tefA phylogeny indicated that four endophyte strains isolated from S .purpurea were most closely related to Epichloёchisosa from North American Achnatherum eminens and formed two distinct branches.Four other en-dophyte strains isolated from S .purpurea were most closely related to Epichloёindbrians and Epichloёgan-suensis ,which infect Achnatherum inebrians and these strains formed another distinct branch.In addition,a-nalysis of actG phylogeny indicated that four clarify further endophyte strains isolated from S .purpurea were also most closely related to Epichloёchisosa from North American A.eminens and formed another distinct branch.Other endophyte strains isolated were most closely related to Epichloёgansuensis from China (Xin-jiang)and formed another distinct branch.Our results suggest that the host-specificity might not occur in en-dophytes infecting S .purpurea and S .purpurea appears to be infected by various Epichloёspecies.关键词
青藏高原/紫花针茅/内生真菌/系统发育/宿主Key words
Qinghai-Tibet Plateau/Stipa purpurea/Epichloё/phylogeny/host引用本文复制引用
鲍根生,李春杰..青藏高原高寒草地优势禾草－紫花针茅内生真菌分离和鉴定[J].草业学报,2016,25(3):32-42,11.基金项目
国家973计划课题（2014CB138702），国家自然科学基金项目（31372366），教育部创新团队发展计划项目（IRT13019）和公益性行业（农业）科研专项经费项目（201203041）资助。 （）
