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

PurposeTo 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.

MethodFour 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 flue-cured tobacco rhizosphere soil after application of organic fertilizer.

ResultThe 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.

ConclusionBased 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.