巨桉人工林外生菌根真菌群落组成及多样性

Composition and Diversity of Ectomycorrhizal Fungal Community Associated with Eucalyptus grandis Plantation

研究巨桉人工林外生菌根(ECM)真菌群落组成及多样性,为菌类资源的开发利用和人工林的可持续经营提供参考依据。以赣南地区6个不同林龄的巨桉人工林为研究对象,采用高通量测序方法,鉴定分析巨桉根系ECM真菌群落组成及多样性。本研究共得到1 929个OTU,隶属于2门2纲10目22科30属。革菌属(Thelephora)、硬皮马勃属(Scleroderma)、棉革菌属(Tomentella)为研究区内优势菌属,总相对丰度超过80%。三大优势菌属在不同林龄林分中分布情况明显不同,相似性分析和非度量多维尺度分析结果也显示,不同林龄林分ECM真菌群落结构存在显著差异。其中2 a和7 a林分ECM真菌群落结构相似性最高,表现为物种丰富度、均匀度较高;3 a和6 a林分ECM真菌物种数量差异大,3 a和9 a林分ECM真菌种类差异大。表明巨桉人工林ECM真菌群落主要由3种丰度较高的优势菌属与多种低丰度菌属共同组成,林龄是影响巨桉人工林ECM真菌群落结构的重要因素。

To provide references for the utilization of fungal resources and sustainable management of plantations,the composition and diversity of ectomycorrhizal(ECM)fungi associated with Eucalyptus grandis roots were studied.Six E.grandis plantations with different stand ages in Southern Jiangxi were selected as study objects.ECM fungal community composition and diversity were identified and analyzed by using high-throughput sequencing method.A total of 1929 OTU(operational taxonomic unit)were obtained,belonging to 30 genera,22 families,10 orders,2 classes and 2 phyla.Thelephora,Scleroderma and Tomentella were the dominant genera with a total relative abundance of over 80%.The distributions of these three in stands with different ages were different,and the results of similarity analysis and non-metric multi-dimensional scaling analysis also suggested that there were significant differences in ECM fungal community among all stand ages.Particularly,2 a and 7 a stands were the most similar,in aspects of the ECM fungal communities,with high abundance and uniformity.There was a great difference in the number of species between 3 a and 6 a stands.The species composition of 3 a and 9 a stands were obviously different.In conclusion,ECM fungal community of E.grandis plantations is mainly composed with 3 kinds of core genera with high abundance and a variety of low abundance genera,and stand age is an important factor affecting ECM fungal community of E.grandis plantation.