施用有机肥对烤烟根际土壤细菌群落多样性的影响

Effect of Organic Fertilizer Application on Bacterial Community Diversity in Rhizosphere Soil of Flue-cured Tobacco

【目的】研究施用有机肥对烤烟根际土壤细菌群落多样性的影响,为烟区土壤改良提供科学依据。【方法】设置单施化肥、增施烟草专用有机肥、生物有机肥和精制有机肥4个处理,运用高通量测序技术对有机肥施用后烤烟根际土壤细菌群落结构组成、多样性及功能预测进行分析。【结果】增施有机肥后,烤烟根际土壤细菌群落Shannon指数、Chao 1指数及特有细菌菌种数量均有所提高,表现为生物有机肥>精制有机肥>烟草专用有机肥。增施有机肥处理的烤烟根际土壤中变形菌门(Proteobacteria)、酸杆菌门(Acidobacteria)、芽单胞菌门(Gemmatimonadetes)、绿弯菌门(Chloroflexi)和浮霉菌门(Planctomycetes)等优势门及鞘氨醇单胞菌属(Sphingomonas)、黄色土源菌属(Flavisolibacter)、Bryobacter和芽单胞菌属(Gemmatimonas)等优势属的相对丰度较单施化肥处理均有所增加,但放线菌门(Actinobacteria)相对丰度降低。细菌群落功能预测结果表明:增施有机肥有利于提高烤烟根际土壤中化能异养、几丁质分解、光养、光异养、硝化和发酵等功能性细菌群落的相对丰度。【结论】在施用化肥的基础上配施有机肥有利于提高烤烟根际土壤细菌群落多样性、丰富度及功能性细菌群落的相对丰度,其中以施用烟草专用有机肥表现更为突出,有利于提高土壤细菌群落多样性,促进土壤碳氮代谢。

[Purpose]To provide scientific basis for the improvement of soil in tobacco area,the effect of organic fertilizer application on the diversity of bacterial community in rhizosphere soil of flue-cured tobacco was studied.[Method]Four treatments were set up:single application of chemical fertilizer,increasing application of special organic fertilizer for tobacco,application of bio-organic fertilizer and application of refined organic fertilizer.The high-throughput sequencing technology was used to analyze the composition,diversity and function prediction of bacterial community in fluecured tobacco rhizosphere soil after application of organic fertilizer.[Result]The Shannon index,Chao 1 index and the population of special bacteria in flue-cured tobacco rhizosphere soil were increased by organic fertilizer application,which showed that bio-organic fertilizer>refined organic fertilizer>special organic fertilizer for tobacco.In the rhizosphere soil of flue-cured tobacco treated with organic fertilizer,the relative abundances of the dominant phylum such as Proteobacteria,Acidobacteria,Gemmatimonadetes,Chloroflexi,Planctomycetes and dominant genus such as Sphingomonas,Flavisolibacter,Bryobacter and Gemmatimonas increased compared with the treatment of single chemical fertilizer,but the relative abundances of Actinobacteria decreased.The prediction results of bacterial community function showed that the application of organic fertilizer increased the relative abundance of functional bacterial community in rhizosphere soil of flue-cured tobacco,such as chemoheterotrophy,chitinolysis,phototrophy,photoheterotrophy,nitrification and fermentation.[Conclusion]Based on the application of chemical fertilizer,increasing the application of organic fertilizer can improve the diversity,richness and relative abundance of functional bacterial community in rhizosphere soil of flue-cured tobacco.Among them,the application of tobacco special organic fertilizer is more prominent,which is conducive to improve soil bacterial community diversity and promote soil carbon and nitrogen metabolism.