Effects And Correlation Analysis Of Soil Conditioner On Microbial Community In Tobacco Field Of Liangshan Prefecture

In this study,two different soil conditioners were applicated in Huili County and Dechang County,Liangshan Prefecture,in order to improve tobacoo-planting soil and increase yield.The microbial diversity,community composition and structure of tobacco rhizosphere soil were detected by the use of high-throughput sequencing technology.The nutrient contents and enzyme activities in tobacco rhizosphere soil were also tested.The effects of soil conditioners on rhizosphere soil microflora at different tobacco plant growth stages were analyzed.The correlation between microbial community and environment factor were discussed,which can provide a theoretical support for improving tobacco planting soil in Liangshan Prefecture.The results are as follows :(1)The richness and diversity of tobacco rhizosphere soil bacterial community were increased by the application of high biochar soil conditioner and high calciummagnesium soil conditioner at different tobacco plant growth stages.There were regional variances about the effects of soil conditioner on Alpha diversity.The Alpha diversity of the soil fungal community in Huili County were increased by the application of two soil conditioners.The richness of the soil fungal community in Dechang County were reduced by the application of high calcium-magnesium soil conditioner,while the high biochar soil conditioner remained unchanged(2)The rhizosphere soil microflora were constant changed with the growth of tobacco,especially at the vigorous growth stage.The relative abundance of beneficial microbes such as Arthrobacter,Sphingomonas,Chujaibacter,Arachidicoccus and Aspergillus etc.were increased by the application of soil conditioner.There were variances in soil microorganisms between the soil conditioners treatment and control group in different tobacco production areas.Planctomycetacia,Ktedonobacteraceae,Isosphaerales,Legionellale,Polyangiaceae,Bacteroidetes and Chthonomonadetes were the main differential microorganisms in rhizosphere soil of tobacco fields in Huili County.Cyanobacteria,Synechococcus,Microlunatus,Arenimonas,Parapedobacter and Bacteriovoracaceae were the main differential microorganisms in rhizosphere soil of tobacco fields in Dechang County.(3)There were variances about the relationship between soil environment factor and soil microbial community in different tobacco production areas.The rhizosphere soil bacterial community in Huili County tobacco fields showed large correlation with organic matter,p H,available potassium,urease and invertase.While the rhizosphere soil fungal community showed large correlation with p H,available phosphorus,available potassium,acid phosphatase,catalase,invertase and urease.Arthrobacter showed significant positive correlation with catalase,p H and urease.The rhizosphere soil bacterial community in Dechang County tobacco fields showed large correlation with organic matter,p H,available phosphorus,acid phosphatase,invertase,catalase and urease.While the rhizosphere soil fungal community showed large correlation with invertase and proteases.Chujaibacter showed significant positive correlation with catalase and proteases.Fusarium showed significant negative correlation with hydrolyzable nitrogen.(4)The p H value of Huili County and Dechang County tobacco field were increased 0.13 and 0.65 respectively at maturity,the available phosphorus were increased 4.30% and 8.69% respectively,the available potassium were increased 6.23%and 28.75% respectively,the yield were increased 7.08% and 17.10% respectively,the output were increased 17.73% and 26.20% respectively by the application of high biochar soil conditioner.The p H value of Huili County and Dechang County tobacco field were increased 0.48 and 0.51 respectively at maturity,the available phosphorus were increased 4.97% and 13.00% respectively,the available potassium were increased3.18% and 20.78% respectively,the yield were increased 38.94% and 22.10%respectively,the output were increased 41.08% and 41.69% respectively by the application of high biochar soil conditioner.The p H value,nutrient content and enzyme activity in rhizosphere soil of tobacco fields in Liangshan Prefecture were increased to a different degree by the application of soil conditioner.The soil conditioner also can promote the growth of tobacco plant,reduce the incidence of climate spot,increase yield and output.