中文摘要：

对广东省不同地区意大利黑麦草根际VA菌根的形成规律和营养环境条件（含水量、pH值、土壤温度、土壤养分等）进行了研究。结果表明，在广东省不同地区意大利黑麦草根系中普遍存在AMF（Arbuscular mycorrhiza fungi）的感染，但AMF对意大利黑麦草的感染不存在地带性特征。除菌丝感染外，还发现有大量的丛枝状结构和泡囊状结构。AM总感染率、菌丝感染率、丛枝感染率以及泡囊感染率都与土壤全P、速效P含量极显著负相关（P〈0．01）。不同地区黑麦草根际土壤中含有的AMF孢子数量存在差异，AMF孢子总数与AM丛枝感染率、AM泡囊感染率极显著正相关（P〈0．01）。AMF孢子总数与土壤含水量、有机质含量、全N含量、水解N含量极显著正相关（P〈0．01）；与全P含量显著负相关（P〈0．05）。土壤理化性状、地域以及环境因子的不同，可能是导致了不同地方AMF数量差异的主要原因。研究结果对水田管理和科学施肥具有指导意义。

英文摘要：

In this study, we investigated the formation rules, the nutritional and environmental conditions （moisture, pH value, soil temperature, soil nutrient, etc. ） of the VA mycorrhizal in Italian ryegrass rhizosphere in different areas of Guangdong province. Our results showed that, the AMF colonization in Italian ryegrass root system is universal in different areas of Guangdong, but the AMF colonization in Italian ryegrass showed no regional characteristic. Besides the colonization of mycelium, a large number of AM structures of arbuscules and vesicles were also found. The total AM infection rates, the mycelium infection rates, the arbuscule infection rates and the vesicle infection rates all had significant negative correlations with soil total phosphorus and soil available phosphorus （p 〈 0. 01 ）. There were differences in the quantity of spores contained in Italian ryegrass rhizosphere in different areas of Guangdong. The number of the total AMF spores had significant positive correlations with the AM arbusculear infection rates and the AM vesicle infection rates （p 〈 0. 01 ）. It also had significant positive correlations with the soil moisture, organic matter, total nitrogen and soluble nitrogen （p 〈 0. 01 ） , and a significant.negative correlation with the soil total phosphorus （p 〈0. 05）. The differences of soil physical and chemical characters, regional and environmental factors may be the main factors inducing the differences of AMF quantity in different areas. The results may be applied to the management of paddy field and to the efficient fertilization.