不同有机物料强还原处理对植烟土壤微生物群落的影响

Effect of Reducing Soil Disinfestation with Different Organic Materials on Microbial Community at Tobacco Planted Soil

【目的】本文探究了在厌氧强还原条件下,豆渣、甘蔗渣单施及其等比例混合物施用后,不同处理间土壤理化性质与微生物群落变化的相关关系。【方法】应用Tax4Fun及FUNGuild分别对细菌和真菌群落进行功能预测,采用Vegan和pheatmap等R语言软件包完成统计分析和绘图,利用生物信息学方法分析不同样本中微生物群落结构和多样性变化,确定微生物与RSD技术之间的相关性。【结果】结单一用蔗渣和豆渣的RSD处理都提高了真菌群落丰富度。在门的水平上,放线菌(Actinobacteria)、厚壁菌门(Firmicutes)、酸菌门(Acidobacteria)、子囊菌门(Ascomycota)和担子菌门(Basidiomycota)的相对丰度发生变化,揭示了处理间群落结构存在显著差异。此外,RSD还有效降低了镰刀菌属(Fusarium)、链格孢属(Alternaria)等土传病原菌的丰度。斯皮尔曼相关性分析说明全氮、全磷、碱解氮、速效钾、pH和有机质是造成群落结构差异的主要影响因子。功能注释结果显示RSD技术能提高土壤中细菌群落萜类和多酮类化合物代谢的功能活性及腐生真菌的丰度。【结论】单独施用豆渣的RSD处理可以通过促进土壤肥力的提升及土壤健康群落重构来缓解植烟土壤连作障碍,是一种优良的控制土传病害的技术手段。

[Objective]As an important cash crop in China,tobacco has been suffering from the continuous cropping obstacle in the planting process.Reductive soil disinfestation(RSD)could be an effective way to alleviate continuous cropping obstacles,while its effects on the structure and function of the microbial community in tobacco soil were rarely reported.The correlation between the changes of soil properties and microbial community under various RSD treatments was investigated by using bean dregs,sugarcane bagasse,and their mixtures in equal proportion.[Method]The Tax4Fun and Funguild were used to predict the function of bacterial and fungal communities respectively,and used R language software packages such as Vegan and pheatmap to complete statistical analysis and drawing.Moreover,bioinformatics methods were used to analyze the changes of microbial community structure and diversity in different samples to determine the relationship between microorganisms and RSD technologies.[Result]The abundance of fungi was increased with addition of bagasse or okara.The relative abundances at the phylum level such as Actinobacteria,Firmicutes,Acidobcteria,Ascomycota and Basidiomycota were changed,revealing the difference in community structure between different treatments.In addition,RSD effectively reduced the abundance of Fusarium,Alternaria and other soil borne pathogens.Spearman correlation analysis showed that total nitrogen,total phosphorus,available nitrogen and potassium,pH and organic matter were the main factors driving community structure differences.Moreover,community function prediction showed that RSD treatment increased the activity of bacteria related to terpenoids and polyketides metabolism as well as the population of saprotroph fungi relative to CK.[Conclusion]Through improving soil fertility and promoting reconstruction of soil healthy microbial community,the RSD treatment with addition of bean dregs alone can alleviate the continuous cropping obstacle of tobacco-growing soil,and also it can be used as an excellent technology to control soil-borne diseases.