中文摘要：

应用相关性分析和通径分析研究了府谷清水川流域砒砂岩区土壤因子对刺槐（Robinia pseudoacacia）和沙棘（Hippophae rhamnoides）根际丛枝菌根真菌（AMF）的影响.结果表明：AMF可以与刺槐和沙棘形成良好的共生关系;从两种植物根际土中共分离鉴定出AMF 13种,其中摩西囊霉（Glomus mosseae）、地球囊霉（Glomus geospo-rum）和缩球囊霉（Glomus constrictum）为优势种;AMF平均侵染率为90.6%,平均孢子密度为559.1个·100 g^-1干土;AMF的孢子密度、侵染率和种类之间没有显著的相关性;刺槐和沙棘根际AMF侵染率均与pH呈显著正相关,在刺槐根际,pH和有效氮通过直接作用影响侵染率,有机质和有效磷通过间接作用影响侵染率;在沙棘根际,pH和有效磷通过直接作用影响侵染率,有机质和有效氮通过间接作用影响侵染率;在沙棘根际,有机质和pH主要是通过直接作用影响AMF种类,有效氮主要通过有效磷的间接作用影响AMF种类.

英文摘要：

The influence of soil factors on arbuscular mycorrhizal fungi in the rhizosphere of Robinia pseudoacacia and Hippophae rhamnoides in soft rock zone of Qingshuichuan valley of FuGu were studied by the analysis of correlation and the path analysis of correlation.The results showed that symbiotic relation was formed between AMF and the host plants.Thirteen AMF species were isolated and the average colonization rate of AMF was 90.6%.The average spore density was 559.1·100 g^-1soil and the colonization of AMF had no significant positive correlation with spore density and species.The colonization rate had significant positive correlation with pH in the rhizosphere of R.pseudoacacia and H.rhamnoides.In the rhizosphere of R.pseudoacacia,pH and available N influenced colonization rate directly,while available P and organic matter influenced colonization rate indirectly.In the rhizosphere of H.rhamnoides,pH and available P influenced colonization rate directly,organic matter and available N influenced colonization rate indirectly.In the rhizosphere of H.rhamnoides,pH and organic matter influenced species of AMF directly,available N influenced species of AMF indirectly.