梵净山4种林型的土壤丛枝菌根真菌多样性

摘要

Thirteen rhizospheric soil samples were collected from four types of forest(Phyllostachys edulis, Cryptomeria japoni-ca,Camellia japonica,and Fargesia spathacea)in Fanjingshan National Nature Reserve(FNNR).The Arbuscular Mycor-rhizal Fungi(AMF)spores were isolated by wet-sieving and sucrose centrifugation methods,and then AMF species were i-dentified based on morphological characters.The results indicate that AMF species is varied,has identified 10 genera and 20 species,including Glomus and Acaulospora is dominant genus, Glomus deserticola and Scutellospora calosporais com -mon species.AMF diversity is closely related to forest type,and the spore density,species richness and dominate species are different in different forest types rhizosphere soil,AMF diversity characterized by the following trends:the less of AMF species richness,the greater the fungal spores density, the higher the dominance of dominant species(like the forest of Phyllostachys edulis).The more of AMF species richness, the small fungal spore density is, the lower the dominance of dominant species(like the forest of Camellia japonica)is.%采用湿筛倾析-蔗糖离心法和形态鉴定法,调查了梵净山国家级自然保护区毛竹(Ph yllostachys ed u-lis)林、柳杉(Crypt omeria japonica)林、山茶(Camellia japonica)林和箭竹(Fargesia spathacea)林根围土壤丛枝菌根(AM)真菌种类.结果表明:梵净山4种林型根围土壤中AM真菌种类丰富,已确定10属20种,球囊霉属(Glo-mus)和无梗囊霉属(Acaulospora)为优势属,沙荒球囊霉(Glomus deserticola)和美丽盾巨孢囊霉(Scutellospora calos-pora)为共有种.土壤AM真菌多样性与林型密切相关,不同林型根际土壤AM真菌的孢子密度、物种丰富度和优势种都不同.4种林型 AM真菌多样性表现为以下趋势:AM真菌的物种丰富度越小,真菌孢子密度就越大,优势种的优势度就越高(例如毛竹林);AM真菌的种类越多,真菌孢子密度就越小,优势种的优势度就越低(例如山茶林).