西藏不同生态环境下藏麻黄可培养内生真菌及根际土壤真菌多样性

Diversity of culturable endophytic fungi and rhizosphere soil fungi in Ephedra saxatilis Royle ex Florin under different ecological environments in Tibet

藏麻黄(Ephedra saxatilis Royle ex Florin)是西藏地区特有种,是重要的藏药资源,具有发散风寒、发汗平喘和抗肿瘤等功效。植物相关微生物会影响植物生长发育,并且部分内生真菌影响药用植物有效活性成分的合成。通过比较荒漠草原环境(GHS)和高寒草原环境(GHC)生长的藏麻黄植物内生真菌及根际土壤真菌的群落结构及多样性,挖掘生境差异的真菌组成,以揭示藏麻黄植物的适应性机制,以及挖掘药用真菌资源。通过可培养技术,分离和纯化不同环境藏麻黄根际土壤真菌和根、茎组织内生真菌,并利用ITS区域序列进行分析鉴定。最终得到根际土壤真菌49株,鉴定为15属24种,获得内生真菌54株,鉴定为19属25种。在荒漠草原环境和高寒草原环境生长的藏麻黄根际土壤真菌分别注释到8属13种和7属12种,植物内生真菌分别注释到9属12种和14属16种。多样性分析结果表明,不同环境下菌群的alpha多样性无显著差异。藏麻黄及其根际土壤具有丰富的可培养真菌资源,不同环境的真菌及内生真菌群落结构差异较大。分离、纯化的菌株为进一步开发利用功能菌株资源提供材料。

Ephedra saxatilis Royle ex Florin is endemic to Tibet and is an important resource of Tibetan medicine,which has the effect of dispersing wind-cold,diaphoresis,relieving asthma and antitumor.Plant related microorganisms can affect plant growth and development and some endophytic fungi can affect the synthesis of active components in medicinal plants.To reveal the adaptive mechanism of Ephedra saxatilis Royle ex Florin,and to explore its resources,the fungal compositions of different habitats were analyzed by comparing the community structure and diversity of endophytic fungi and rhizosphere soil fungi growing in desert steppe environment(GHS)and alpine grassland environment(GHC).Rhizosphere soil fungi and root,stem endophytic fungi were isolated from Ephedra saxatilis Royle ex Florin in different environments by pure culture,purified,and identified based on ITS sequence analysis.A total of 49 phyllospheric strains(24 species in 15 genera)were identified from rhizosphere soil including 13 species in 8 genera collected from GHS,and 12 species in 7 genera collected from GHC.A total of 54 phyllospheric strains were identified in plant endophytic fungi including 12 species in 9 genera collected from GHS and 16 species in 14 genera collected from GHC.The results of diversity analysis showed that there was no significant difference in alpha diversity of microflora in different environments.There are abundant resources of culturable fungi in Ephedra saxatilis Royle ex Florin and its rhizosphere soil.The community structure of fungi and endophytes varies greatly in different environments.The isolated and purified strains provide materials for further development and utilization of functional strain resources.