云南广南天然蒜头果可培养内生及根际真菌多样性分析

Diversity of Cultivable Endophytic and Rhizosphere Fungi from Natural Malania oleifera in Guangnan County of Yunnan

为探讨蒜头果内生、根际真菌与其存活、生长及生境的关系,在云南广南县蒜头果天然分布区选取3个代表不同生境的样地,采集蒜头果根、茎、叶和根际土进行内生、根际真菌的分离鉴定及其群落结构多样性分析。结果表明:3个样地共分离获得蒜头果内生、根际土壤真菌276株,涉及3个门8个纲35个属,其中木霉属,间座壳属和青霉属为优势菌属。不同部位中茎部内生菌种类和数量最为丰富,共93株,24个属,且多样性、均匀度及丰富度指数最高。此外,根部内生菌和根际真菌的群落组成相似性系数最高,而叶部内生菌最低。在相同海拔条件下,裸露石灰岩山地(DY)与石灰岩林地(DB)的蒜头果内生、根际真菌群落组成具有一定的相似性,但前者较后者丰富;石灰岩林地中,低海拔生境(DB)的蒜头果内生、根际真菌群落组成较高海拔生境(NZ)丰富,且二者群落结构差异较大。不同生境间蒜头果内生、根际真菌多样性与丰富度指数为裸露石灰岩山地(DY)>低海拔石灰岩林地(DB)>高海拔石灰岩林地(NZ),而优势度与均匀度指数则相反。由此表明,裸露石灰岩山地(DY)的蒜头果内生、根际真菌群落更为丰富,而高海拔石灰岩林地(NZ)的单菌属优势突出,菌落结构较为单一。

In order to explore the relationship between endophytic and rhizosphere soil fungi of Malania oleifera and host survival,growth and habitat,3 sample plots representing different habitats were selected in the natural distribution area of M.oleifera in Guangnan County,Yunnan Province,and the roots,stems,leaves and rhizosphere soil of M.oleifera were collected for isolation,identification and the analysis of community structure diversity.The results showed that 276 endophytic and rhizosphere soil fungi were isolated from 3 different plots,involving 3 phyla,8 classes and 35 genera,among which Trichoderma,Diaporthe and Penicillium were the dominant genus.The species and number of endophytic fungi in stems were the most abundant,with 93 strains and 24 genera,as well as the Shannon-Wiener index,evenness index and Margalef index were the highest.In addition,the similarity coefficient of community composition between root and rhizosphere fungi was the highest,while the similarity coefficient between root and leaf was the lowest.At the same altitude conditions,the community composition of endophytic and rhizosphere fungi of M.oleifera in bare limestone mountain(Yangmaba,Dongbao Township,DY)and limestone woodland(Bajiao mountain,Dongbao Township,DB)had certain similarity,while the former was richer than the latter;in limestone woodlands,the community composition of endophytic and rhizosphere fungi of M.oleifera in low altitude habitat(DB)was richer than that in the high altitude habitat(Zhuangke Village,Nanping Town,NZ),and the differences between them was significant.The ShannonWiener indexs and Margalef indexes of endophytic and rhizosphere fungi of M.oleifera in different habitats were bare limestone mountain(DY)>low-altitude limestone woodland(DB)>high-altitude limestone woodland(NZ);while the Simpson indexes and Evenness indexes were opposite.Therefore,the endophytic and rhizosphere fungi communities of M.oleifera in exposed limestone mountain(DY)are more abundant,while the single genus advantage of high-altitude limestone woodland was dominant,and the colony structure was relatively simple.