山东省不同地区棉花内生真菌的多样性和群落结构分析

Analysis of Community Structure and Diversity of Endophytic Fungi from Cotton in Different Areas of Shandong Province

【目的】内生真菌能够促进植物生长,提高植物抵御外界不良环境的能力。本文旨在对棉花内生真菌的群落结构和多样性进行系统分析,明确内生真菌资源分布,同时探讨生长环境与内生真菌群落结构和多样性的关系。【方法】在山东省19个地区采集棉花叶片,运用马铃薯葡萄糖(Potato dextrose agar)培养基进行内生真菌的分离、纯化、保存,采用内转录间隔区(Internal transcribed spacer)序列分析技术进行种属鉴定,并对分离得到的内生真菌进行群落结构和生物多样性分析。【结果】19个地区的棉花取样中,共分离得到134个菌株归属于15个属(包括Alternaria、Fusarium、Diaporthe、Penicillium、Stemphylium、Bipolaris、Epicoccum、Curvularia、Nigrospora、Botryosphaeria、Lichtheimia、Gibellulopsis、Phaeosphaeria、Cladosporium、Setosphaeria)。依据相对分离率,山东省的棉花内生真菌优势属为Alternaria(77.12%)。具体分析,滨州市滨城区和桓台的优势属为Fusarium(66.67%、100.00%),曹县的优势属为Alternaria (50.00%)、Fusarium(50.00%),济阳的优势属为Alternaria(37.50%)和Setosphaeria(37.50%)。不同地区内生真菌定植率差异显著,其中最高的是垦利(85%),其次为茌平(70%)、无棣(60%),而惠民、邹城的最低(5%)。根据Shannon-Weaver指数,济阳棉花内生真菌生物多样性最高(1.26),其后依次为茌平(1.15)、滨州市滨城区(0.87)、曹县(0.69)、郓城(0.64)、无棣(0.59)、垦利(0.57)、金乡(0.51)、商河(0.35),成武、东阿、高唐、惠民、聊城市东昌府区、夏津、阳谷、鱼台、邹城、桓台仅鉴定出1种棉花内生真菌,生物多样性最低。19个地区内生真菌聚成2个类群,一类是茌平、无棣、垦利,此类内生真菌定植率高,鉴定出的菌属数目多,其他地区聚为一类,内生真菌种类少,定植率低。【结论】山东省棉花内生真菌具有丰富的多样性。地域对内生真菌的分布具有一定的影响。

[Objective]Endophytic fungi can promote plant growth and enhance plant resistance to adverse environments.This article analyzed the community structure,biodiversity and distribution of endophytic fungi from cotton plants,and discusses the potential relationship between endophytic fungi community structure and biodiversity and the growing environment.[Method]Cotton leaves were collected from 19 areas in Shandong province,China.The endophytic fungi were isolated,purified and conserved with potato dextrose agar medium.After identification by internal transcribed spacers,the community structure and diversity were analyzed.[Result]The results showed that 134 strains and 15 genera(Alternaria,Fusarium,Diaporthe,Penicillium,Stemphylium,Bipolaris,Epicoccum,Curvularia,Nigrospora,Botryosphaeria,Lichtheimia,Gibellulopsis,Phaeosphaeria,Cladosporium,Setosphaeria)were obtained.Alternaria(77.12%)was the dominant genus of endophytic fungi in Shandong province.Fusarium was the dominant genus in the Bincheng district of Binzhou(66.67%),and Huantai(100.00%),while Alternaria(50.00%)and Fusarium(50.00%)were the dominant genera of Caoxian,and Alternaria(37.50%)and Setosphaeria(37.50%)were the dominant genera of Jiyang.There were significant differences in the colonization rate in different areas.The highest colonization rate appeared in Kenli(85%),followed by Chiping(85%)and Wudi(60%),while the lowest colonization rate appeared in Huimin and Zoucheng(5%).According to the Shannon-Weaver index,Jiyang had the highest diversity index(1.26),followed by Chiping(1.15),the Bincheng district in Binzhou(0.87),Caoxian(0.69),Yuncheng(0.64),Wudi(0.59),Kenli(0.57),Jinxiang(0.51),and Shanghe(0.35).Only single genera,Alternaria,were found in each of the locations Chengwu,Dong'e,Gaotang,Huimin,the Dongchangfu district in Liaocheng,Xiajin,Yanggu,Yutai,Zoucheng and Huantai.Cluster analysis showed that the 19 geographic areas could be classified into two groups.One group included Chiping,Wudi and Kenli,which had a higher colonization rate and more genera;the other one had a lower colonization rates and fewer genera.[Conclusions]The endophytic fungi in cotton were highly diverse.The distributions of endophytic fungi were distinct among regions in Shandong province.