Mechanism of phosphate accumulation and translocation in arbuscdar mycorrhizal assodation and its application to environmental restoration

一、菌丝多聚磷酸盐转运速率的分析我们建立了一种用多聚磷酸酶/荧光素酶系统定量测定丛枝菌根真菌菌丝中多聚磷酸盐(Polyp)的方法。在酸性(pH 4.3)和中性(pH 7.0)条件下，比较了球孢霉HR1、细链孢霉OK-15和球囊霉与日本莲花共生时的息肉移位率。球藻(Glomus sp.)从酸性土壤中分离到的HR1和细链霉菌OK-15在pH值为4.3和7.0时对寄主生长有促进作用。而中性土壤中的赤霉菌只在pH为7.0时才能定殖并促进寄主生长，而在pH为4.3时不定殖。球菌体的息肉移位率。在酸性硫酸盐土中丛枝菌根真菌的生态研究我们成功地从日本爱知县哈祖町和北海道兰科市的先锋植物根际分离到丛枝菌根真菌。经鉴定，球藻属(Glomus sp.)Hr1分离自Aichi和Glomus sp.根据18S rRNA基因的系统发育分析，来自北海道的Rf1真菌属于同一类群，这表明这些真菌适应酸性环境。通过盆栽试验，以几种先锋植物根际土壤为材料，研究真菌多样性对先锋植物生长的影响。植物在土壤中的生长量较大，表现出较高的真菌多样性，表明真菌多样性对先锋植物的生存和生长具有重要意义。

I.Analysis of the rate of polyphosphate translocation through hyphaeWe have established a method to quantify polyphosphate (polyP) in hyphae of arbuscular mycorrhizal fungi using the polyphosphate kinase/luciferase system. The rate of polyP translocation was compared between Glomus sp.HR1, Archaeospora leptoticha OK-15 and Glomus etunicatum in symbiosis with Lotus japonicus under acidic (pH 4.3) and neutral (pH 7.0) conditions. Glomus sp. HR1 and A.leptoticha OK-15 which were isolated from acidic soil promoted the growth of the host at pH 4.3 and 7.0. In contrast, G.etunicatum, an isolate from neutral soil, colonized and promoted the growth of the host only at pH 7.0 but not colonized at pH 4.3. The rate of polyP translocation in Glomus sp. HR1 and A.leptoticha OK-15 was significantly different between the isolates, 1.11 and 0.48 min h^<-1>, respectively, the influence of soil pH on the rate was not observed.II.Ecology of arbuscular mycorrhizal fungi in acid sulfate soilWe succeeded to isolate arbuscular mycorrhizal fungi from the rhizosphere of pioneer plants in acid sulfate soils in Hazu-cho, Aichi and Rankoshi-cho, Hokkaido. It was found that Glomus sp. HR1 from Aichi and Glomus sp. RF1 from Hokkaido belonged to the same cluster based on a phylogenetic analysis of 18S rRNA gene, this suggested that these fungi adapted to acidic environment. The involvement of fungal diversity in the growth of pioneer plants was investigated by a pot experiment using rhizosphere soil collected from several pioneer plants. The growth of the plants was greater in the soil showing higher fungal diversity, indicating the significance of fungal diversity in the survival and growth of the pioneer plants.