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

我们建立了一种利用多磷酸激酶/荧光素酶系统定量测定丛枝菌根真菌菌丝中多磷酸盐（polyP）的方法。在酸性（pH4.3）和中性（pH7.0）条件下，比较了与百脉根共生的球囊霉（Glomus sp.HR1）、细鳞毛孢菌（Trichospora leptoticha OK-15）和球囊霉（Glomus etunicatum）的聚磷转运速率。从酸性土壤中分离到的球囊霉（Glomus sp.HR1）和细毛球囊霉（A.leptoticha OK-15）在pH 4.3和7.0时对寄主有促进作用。相比之下，来自中性土壤的分离物G.etunicatum仅在pH 7.0下定殖并促进宿主生长，但在pH 4.3下不定殖。聚磷转运的速率在球囊霉属HR 1和A.leptoticha OK-15菌株之间有显着差异，分别为1.11和0.48 min h^<-1>，土壤pH值的影响，对该速率没有观察到。II.丛枝菌根真菌在酸性硫酸盐土壤中的生态我们成功地分离出丛枝菌根真菌从先锋植物根际的酸性硫酸盐土壤中的爱知县和北海道的Rankoshi-cho。根据18 S rRNA基因的系统发育分析，发现爱知县的Glomus sp. HR 1和北海道的Glomus sp. RF 1属于同一个类群，表明这两种真菌均适应酸性环境。通过盆栽试验，研究了先锋植物根际土壤真菌多样性与先锋植物生长的关系。植物的生长在土壤中表现出较高的真菌多样性，表明真菌多样性在先锋植物的生存和生长中的重要性。

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.