连作百香果对土壤理化性质和微生物特性的影响及病原真菌的分离与鉴定

为了分析连作对百香果土壤理化性质及微生物的影响,本研究以种植0（未种植）、1、2、3 a的百香果根际土壤为材料,分析连作百香果对土壤理化指标、自毒潜力、微生物数量的影响,并对连作百香果根际土壤病原真菌进行分离、鉴定。结果表明,随着种植年限的增加,百香果根际土壤pH呈显著下降趋势,土壤总氮、磷、钾含量变化较小,而有效性氮、磷、钾含量及有机质含量呈上升趋势。自毒潜力分析结果表明,与对照（0 a,未种植）相比,种植1、2、3 a的百香果根际土壤对受体莴苣的抑制率分别为39.84%、54.36%、61.83%。微生物数量分析结果表明,随着百香果种植年限的增加,土壤细菌与放线菌数量呈显著下降趋势,而真菌数量呈显著上升趋势。相关性分析结果表明,百香果种植土壤的年限与土壤pH、细菌、放线菌数量呈极显著负相关,而与土壤有效氮、有效磷、有效钾含量及真菌数量呈显著或极显著正相关。微生物分离与鉴定结果表明,共分离到9种不同类型的真菌,其中真菌BXG 3、BXG 7、BXG 9可显著影响百香果的正常生长;鉴定结果表明,真菌BXG 3、BXG 7、BXG 9分别为层出镰刀菌（Fusarium proliferatum）、棕黑腐质霉菌（Humicola fuscoatra）和毛栓菌（Trametes hirsute）。

Effects of Continuous Cropping Passion Fruit on Soil Physicochemical Property,Microbial Characteristics and Isolation,Identification of Pathogenic Fungi

In order to analyze the effect of continuous cropping of passion fruit on the soil physicochemical property and microorganism,the rhizospheric soils cultivated for 0,1,2 and 3 years were used as the materials.Soil physical and chemical indicators,autotoxicity potential,and microbial quantity were analyzed.Furthermore,the pathogenic fungi in rhizosphere soil were isolated and identified.The results showed that the pH value of the passion fruit rhizosphere soil showed a significant downward trend with the passage of planting.Total nitrogen,phosphorus and potassium content changed little,while available nitrogen,phosphorus,potassium and organic matter content increased.The results of autotoxicity potential analysis showed that the inhibition rates of 1-,2-,3-year-old rhizosphere soil on lettuce was 39.84%,54.36%and 61.83%,respectively,compared with the control(0 years).The results of microbial quantitative analysis indicated that the number of soil bacteria and actinomycetes decreased significantly with the passage of planting,while the number of fungi increased significantly.Correlation analysis suggested that the planting years of the passion fruit soil was significantly negatively correlated with pH value,and the content of bacteria and actinomycetes,but significantly positively correlated with the content of available nitrogen,available phosphorus,available potassium and the number of fungi.The results of microbial isolation showed that nine different kinds of fungi were isolated,and the fungi of BXG 3,BXG 7 and BXG 9 could significantly affect the growth of passion fruit.The identification results showed that BXG 3,BXG 7 and BXG 9 fungi were Fusarium proliferatum,Humicola fuscoatra and Trametes hirsute,respectively.