中文摘要：

调查具有不同植物群落的金沙江支流普渡河、小江干热河谷中91种常见植物的丛枝菌根真菌的侵染率及孢子密度。普渡河样地凋查了56种植物，其中54种（96％）植物能形成典型的丛枝菌根，其平均孢子密度为1423±175／100g土；小江样地35种植物中有34种（97％）植物能形成典型的丛枝菌根，其平均孢子密度为601±103／100g土。单因素方差分析表明两个样地植物的AMF总感染率差异不显著，但其根际土壤中AMF孢子密度却存在显著差异，小江样地的AMF孢子密度明显低于普渡河样地。相关性分析表明，干热河谷植物的AMF感染率与其根际土壤中的AMF孢子密度之间不存在相关性。此外，调查还发现91种植物中，有61种植物（67％）在形成AM的同时，也被黑色有隔内生菌感染。

英文摘要：

Arbuscular mycorrhizal （AM） fungal colonization and spore densities of rhizosphere soil of 91 plant species distributed in the tributary dry-hot valleys （Puduhe ＆ Xiaojiang） of Jinsha River were investigated. In Puduhe, 54 out of 56 plant species （about 96%） formed typical arbuseular mycorrhiza with an average spore density of 1423 ± 175 spores per 100 g soil, whereas the relative statistic data from Xiaojiang were 34 out of 35 plant species （about 97%） with an average spore density of 601 ± 103 spores respectively. One way analysis of variance （ANOVA） showed that sign/ficant difference in spore density between the two sites was existent, but not in AM fungal colonization. The spore density of rhizosphere soil in Xiaojiang was lower than that in Puduhe. Correlation analyses indicated that AM fungal colonization didn＇ t have a sign/ficant correlation with the spore density in the dry-hot valleys. It was also found that 61 out of 91 plant species surveyed （about 67%） were not only colonized by AM fungi but also dark septate endophytes （DSE） in the dry-hot valleys.