内蒙古盐碱土中AM真菌的多样性与分布

在内蒙古盐碱土13种主要植物分离到3属26种AM真菌,其中球囊霉属(Glomus)22种,无梗囊霉属(Acaulospora)3种,原囊霉属(Archaeospora)1种。地球囊霉(Glomus geosporum)和地表球囊霉(Glomus ver-siforme)是该区域盐碱土中的优势种。13种主要植物均能被AM真菌侵染,其中玉米和马蔺的侵染率最高,达100%;根际土壤中AM真菌孢子密度范围为29~182个g-1烘干土,其中稻的孢子密度最高,达182个g-1烘干土;在不同土壤类型条件下植物的菌根侵染率具有明显的差异,其规律为草甸盐土>碱化盐土>盐化草甸土>碱化草甸土;根际土壤中孢子密度以碱化草甸土最高(101个g-1烘干土),其次为碱化盐土、草甸盐土和盐化草甸土。相关分析表明,根际土壤中AM真菌孢子密度与菌根侵染率无显著相关性。

DIVERSITY AND DISTRIBUTION OF ARBUSCULAR MYCORRHIZAL FUNGI IN SALINE ALKALINE SOIL, INNER MONGOLIA

Out of 13 dominant species of plants growing in saline alkaline soil in Inner Mongolia,3 genera,26 species of AM fungi were isolated.Among them 3 species of Acaulospora,1 species of Archaeospora and 22 species of Glomus were identified,and Glomus geosporum and Glomus versiforme were the dominant ones in the region.All the 13 species of plants were susceptible to infection of AM fungi,and Zae mays and Iris lactea were the highest in AM fungal colonization rate,reaching 100%;AM fungal spore density of rhizosphere soil ranged from 29 to 182 ind g-1 dry soil,and among the 13 species,Oryza sativa was the highest(182 ind g-1 dry soil).Furthermore,AM fungal colonization rate of the dominant plants varied with soil types,showing an decreasing order of meadow solonchak>alkalized solonchak>salined meadow soil>alkalized meadow soil,but in terms of AM fungal spore density,alkalized meadow soil was the highest(101 ind g-1 dry soil),followed by alkalized solonchak,meadow solonchak and salined meadow soil.No significant correlation was detected between AM fungal spore density and colonization rate.