古尔班通古特沙漠南缘短命植物根际AM真菌群落特征研究

调查了我国新疆古尔班通古特沙漠南缘雅玛里克山和黑山头典型小半灌木荒漠中分布的6种优势短命植物(ephemeral plants)小车前Plantago minuta、囊瓣顶冰花Gagea sacculifera、黑鳞顶冰花Gagea nigra、伊犁郁金香Tulipa iliensis、鸢尾蒜Ixiolirion tataricum和串珠老鹳草Geranium transversale根际土壤中AM真菌多样性、孢子密度、物种丰度、相对多度、频度、重要值等。共分离到无梗囊霉属Acaulospora和球囊霉属Glomus 23种AM真菌。6种植物根际土壤中AM真菌孢子密度无显著差异。其中球囊霉属占有绝对的优势,频度为100%,相对多度为99.8%,为优势属。聚丛球囊霉G.aggregatum、幼套球囊霉G.etunicatum、近明球囊霉G.claroideum、沙漠球囊霉G.deserticola 4种AM真菌频度、孢子密度、相对多度及重要值都显著高于其它AM真菌种类,为优势种;它们的频度均大于50%,且G.aggregatum>G.claroideum>G.etunicatum>G.deserticola;它们的孢子密度大小顺序为G.aggregatum>G.etunicatum>G.claroideum>G.deserticola,其中G.aggregatum的孢子密度、频度、相对多度和重要值最高。

Community characteristics of arbuscular mycorrhizal fungi associated with ephemeral plants in southern edge of Gurbantunggut Desert

Arbuscular mycorrhizal (AM) fungi of six species of ephemeral plants,Plantago minuta,Gagea sacculifera,Gagea nigra,Tulipa iliensis,Ixiolirion tataricum and Geranium transversale in undershrub of Gurbantunggut Desert (southern edge) were investigated. Species diversity,spore densities,biovolume and community structures of the fungi were analyzed. Twenty-four species of AM fungi belonging to 2 genera,Acaulospora and Glomus,which were isolated from the rhizosphere of the 6 species of ephemeral plants were obtained. G. aggregatum,G. etunicatum,G. claroideum and G. deserticola were dominant,with the frequency of >50% in order of G. aggregatum > G. claroideum > G. etunicatum > G. deserticola. The spore density higher than 1/g soil of the dominant species was ranked as G. aggregatum > G. etunicatum > G. claroideum > G. deserticola.