贺兰山地区青海云杉EM真菌群落组成与多样性

Diversity and Community Constitution of EM Fungi in Forest Communities of Picea crassifolia in Helan Mountains

以贺兰山内蒙古段的南寺和哈拉乌沟两个地区为研究区域,根据不同的海拔高度和生态环境条件选择14个样地进行青海云杉(Picea crassifolia Kom.)外生菌根的采集,并在形态解剖学的基础上,利用高通量测序技术对其外生菌根真菌的物种多样性与群落组成进行研究。通过序列抽提、去除嵌合体、OTU矩阵、序列比对等一系列数据处理后共划分出239个OTUs,通过建立本地数据库进行BLAST序列比对,最终鉴定出与两个地区青海云杉共生的EM真菌分布在18个科、31个属中。其中,两个地区EM真菌的优势属为Sebacina、Hebeloma-alnicola、Wilcoxina、Tomentella-thelephora,且两个地区EM真菌群落组成具有一定的相似性。在此基础上,运用R i386 3.1.2及相关软件包进行了物种累积曲线、非度量多维尺度法(NMDS)、环境拟合、PermANOVA等分析,结果显示,EM真菌的多样性与不同生态环境条件具一定相关性,且决定EM真菌群落组成的主要因素为年平均气温和土壤pH值。

Two areas including Nansi and Halawugou of Helan Mountains in the Inner Mongolia were took as sample area,and all ectomycorrhizal(EM)type associated with Picea crassifolia were collected from 14 sample plots selected in these two sections according to different altitudes and ecological conditions.With morphological and anatomical characteristics,the high-throughput sequencing were used to analyze the diversity and the community constitution of EM fungi associated with P.crassifolia.Through sequence extraction,removal of chimera,OTU matrix,sequence alignment,determination of different classification levels and a series of sequence processing steps,a total of 239 Operational Taxonomy Unites(OTUs)were identified after standardizing by Mothur,and sequence comparison by BLAST,they were belonging to 18 families and 31 genera.Based on the diversity analysis of OTUs and phylogeny.The dominant species of EM fungi in both areas were Sebacina,Hebeloma-alnicola,Wilcoxina and Tomentella-thelephora.The EM fungal community of P.crassifolia in both areas has some similarity in species composition.The analysis on species accumulation curves,non-metric multimensional scaling(NMDS)and PerMANOVA were carried out by using R i386 3.1.2 and related software packages.There was a certain correlation relationship between the diversity and the different ecological environment conditions,and the main factors determining the composition of EM fungal community were annual mean temperature and soil pH value.