羊粪有机肥对洛阳植烟土壤微生物群落结构和功能的影响

Effects of Sheep Manure Organic Fertilizer on Soil Microbial Community Structure and Function in Luoyang Tobacco-Growing Soil

本试验通过研究植烟土壤中微生物群落结构和功能类群对羊粪有机肥的响应,为洛阳烟区应用有机肥改良植烟土壤提供科学依据。试验设4个处理:不施肥(CK)、仅施化肥(T1)、50%饼肥氮+50%化肥氮(T2)、50%羊粪有机肥氮+50%化肥氮(T3),采用高通量测序技术分析烟草旺长期各处理土壤微生物群落结构及功能类群。结果表明:(1)有机肥明显改变了植烟土壤微生物群落结构的alpha多样性。与饼肥处理相比,羊粪有机肥降低了烟草土壤细菌群落结构的多样性和丰富度,但是提高了真菌群落结构的多样性和均匀度。(2)beta多样性分析显示有机肥处理土壤微生物群落结构与单施化肥处理明显不同,羊粪有机肥和饼肥处理间真菌群落结构差异较大。(3)优势细菌类群分析:有机肥增加了放线菌门和变形菌门的相对丰度,降低了酸杆菌门的相对丰度,其中饼肥处理放线菌门丰度增加更为显著,羊粪有机肥处理变形菌门丰度增加幅度较大。LEfSe分析表明,T1处理红色杆菌纲和红色杆菌目显著富集,T2样本中放线菌门、放线菌纲、Frankiales目显著富集,T3处理样本中鞘脂单胞菌科、鞘脂单胞菌目和丙酸杆菌目显著富集。(4)优势真菌类群分析:有机肥增加了子囊菌门的相对丰度,降低了被孢霉门的相对丰度,羊粪有机肥的作用效果低于饼肥。LEfSe分析表明,T1的优势种群为新赤壳属和Paramyrothecium属,T2的优势菌群为发菌科、黄色篮状菌属、散子囊菌目,T3的优势菌群为粪壳菌纲、肉座菌目和葡萄座腔菌目。(5)功能类群分析显示饼肥明显提高了土壤腐生真菌的相对丰度,羊粪有机肥明显增加了土壤动植物病原菌相对丰度,降低了腐生营养型真菌占比,但其中粪腐生菌相对丰度显著高于其他处理。综上所述,羊粪有机肥明显改变了植烟土壤微生物群落结构和功能类群,对真菌类群的影响尤其显著,病原菌相对丰度有增加趋势,在应用中应加以防范。

In this study,the response of microbial community structure and functional groups in tobacco-growing soil to sheep manure organic fertilizer was studied in order to provide scientific bases for the improvement of tobacco-growing soil in Luoyang by using organic fertilizer.Four treatments were set in the experiment as no fertilization(CK),only chemical fertilizer(T1),50%cake fertilizer nitrogen+50%chemical fertilizer nitrogen(T2),50%sheep manure organic fertilizer nitrogen+50%chemical fertilizer nitrogen(T3).High-throughput sequencing technology was used to analyze the soil microbial community structure and functional groups of each treatment in tobacco vigorous growth period.The results were as follows.(1)Organic fertilizer obviously changed the alpha diversity of soil microbial community structure.Compared with T2 treatment,T3 treatment reduced the diversity and richness of bacterial community structure in tobacco soil,but increased the diversity and evenness of fungal community structure.(2)Beta diversity analysis results showed that the soil microbial community structure of organic fertilizer treatments was obviously different from that of chemical fertilizer treatment,and the fungal community structure was greatly different between T3 and T2 treatments.(3)Analysis of dominant bacterial groups showed that organic fertilizer increased the relative abundance of Actinobacteria and Proteobacteria,and decreased that of Acidobacteria.Among them,T2 treatment increased the abundance of Actinobacteria more significantly,and T3 treatment increased that of Proteobacteria more significantly.LEfSe analysis results showed that the Rubrobacteria and Rubrobacterales were significantly enriched under T1 treatment,the Actinobacteriota,Actinobacteria and Frankiales were significantly enriched under T2 treatment,and the Sphingomonadaceae,Sphingomonadales and Propionibacteriales were significantly enriched under T3 treatment.(4)The analysis of dominant fungal groups showed that organic fertilizer increased the relative abundance of Ascomycota and decreased that of Mortierella.The effect of T3 treatment was lower than that of T2 treatment.LEfSe analysis showed that the dominant species of T1 were Neocosmospora and Paramyrothecium,those of T2 were Trichocomaceae,Talaromyces and Eurotiales,and those of T3 were Sordariomycetes,Hypocreales and Pleosporales.(5)Functional group analysis showed that T2 treatment significantly increased the relative abundance of soil saprophytic fungi.T3 treatment significantly increased the relative abundance of soil animal and plant pathogens,and reduced the proportion of saprophytic vegetative fungi,however,the relative abundance of fecal saprophytic fungi was significantly higher than that of the other treatments.In summary,T3 treatment obviously changed the structure and functional groups of microbial communities especially fungal groups in tobacco-growing soil,and the relative abundance of pathogens showed an increasing trend,which should be prevented in application.