Community Stracture Of Ectomycorrhizal Fungi Associate With Fagaceae In A Tropical Montane Rainforest

Ectomycorrhiza (ECM), being a mutualistic symbiont in forest ecosystem, play key roles in regulating carbon and nutrient cycling processe. Typical ECM host plants of family Fagaceae are dominant species in tropical montane rain forest of Hainan Island. Study on diversity, interspecific interactions and community structuring of ECM fungi associated with Fagaceae plant will help to understand mechanism of species coexistance in tropical forest ecosystem.This study had investigated diversity, plant-fungi interaction and community structure of ECM fungi associate with Fagaceae in a permanent plot of tropical montane rainforest of Jianfengling montain in Hainan Island.The results show that,(1)147 OTUs ECM fungi were detected from Fagaceae root fragments in our study plots. These ECM fungal OTUs can be grouped into 20 genera,23 famillies,18 orders and 3 phylums. ECM fungal family of Russulaceae has the highest number of species, followed by Thelephoraceae, Cortinariaceae and Boletaceae. Lactarius aquosus and Cenococcum geophilum, universally distributing in the forest plots, are the most frequent fungi which were detected on 1/3 of root fragments. Species composition of ECM fungal community and frequent of ECM fungal species varied from plots to plots, however compositional diference was reduced when rare species were excluded.(2) Common ECM fungi showed strong host preference to Lithocarpus, Castanopsis, or Quercus. The most frequent ECM fungi, i.e.,Cenococcum geophilum and Lactarius aquosus strongly prefered to associated with one or two host genus. About 1/3 of fungal species formed ECM with at least two host plant genus.(3) Host identity have significant effect on ECM fungal community structuring (12% variances explained).Correlation between spatial structure and species composition were also found in these forest plots.The diversity, interspecific interaction and community structuring of ECM fungi were revealed in Jianfengling tropical montane rain forest. These findings have significant implications on biodiversity conservation, and restoration of disturbed habitat in torpical forest areas.