丛枝菌根真菌的外生菌丝对土壤水稳性团聚体形成的影响  

Effect of External Hyphae of Arbuscular Mycorrhizal Plant on Water-stable Aggregates in Sandy Soil

作　　者：冯固[1] 张玉凤[1] 李晓林[1] 

机构地区：[1]中国农业大学植物营养系,北京100094

出　　处：《水土保持学报》2001年第4期99-102,共4页Journal of Soil and Water Conservation

基　　金：国家自然科学基金资助项目 ( 499610 0 5和 40 0 710 5 0 )

摘　　要：应用三室根箱装置 ,研究了接种丛枝菌根真菌 Glomus mosseae和 Glomus versiform对玉米根分泌物以及菌根真菌外生菌丝对沙土的水稳性大团聚体形成的作用。结果表明 :接种 Glom us mosseae和 Glomus versiform提高了玉米根系分泌物的总量 ,进而增加了根系粘结的土壤重量。菌根菌丝对土壤中 5～ 2 mm水稳性大团聚体形成的贡献为 10 0 % ;在土壤中菌根菌丝的密度分布与 2～ 1mm水稳性团聚体的含量分布是一致的 ,都表现出随着距离根系表面距离的增加而增加的趋势。这些结果说明菌根菌丝直接促进了土壤团聚体的形成 ,对 5～ 2 m m水稳性大团聚体而言 ,没有菌根菌丝的作用就不能形成 ;菌根菌丝对 5～ 2 mm和 2～ 1m m水稳性团聚体的形成主要是通过其分泌物粘结和菌丝网络对土壤的缠绕作用所致 ,菌根菌丝对这两种水稳性团聚体形成的贡献甚至超过了根系的作用。Three-compartment pots were used to investigate the effects of external hyphae of arbuscular mycorrhiza( AM) on water-stable aggre gates of sandy soil. The pot was separated by two 30 μm nylon meshes, an cent ral one for root growth, two outer ones separated by 30 μm nylon mesh through w hich mycorrhizal hyphae could penetrate but roots could not. Maize was used as h ost plants which were inoculated with G.mosseae or G.vesiform or remained non-i noculated. The results were shown that inoculating with G.mosseae and G.versifor m increased the amount of root exudates of maize plant, by which more soil parti cle was sticked on the root surface comparing to non-inoculating treatment. Two AM fungi contributed 100% to the formation of 5~2mm water-stable aggregates. T he content of 2~1mm water-stable aggregates was increased by AM hyphae comparin g to that of non-inoculating treatment. Increasing of the distance from root su rface, the content of 2~1mm water-stable aggregates and the density of AM hypha e showed a increasing trend.These implied that the effects of AM hyphae on forma tion of 5~2mm and 2~1mm water-stable aggregates exceed the effects of maize roo t s. It is concluded that AM hyphae plays an important in formation of water-stab le aggregates in soil.

关 键 词：丛枝菌根真菌 外生菌丝 土壤水稻性团聚体 

分 类 号：S152.4[农业科学—土壤学] S154[农业科学—农业基础科学]