Effects of Organic Fertilizer Application on Soil Bacterial Polymorphism in Tobacco Fields

In order to achieve the goal of tobacco soil conservation, two compound organic fertilizers OFN and OFJ and tobacco straw organic fertilizer TS were applied to continuous cropping tobacco fields. The Solexa genome analysis platform was employed to determine the soil bacterial polymorphism using the high-throughput sequencing technology. Compared with applying chemical fertilizers only, the bacterial OTU, chao1 and ace in tobacco soils increased when treated with organic fertilizers, indicating the soil bacterial richness increased. The bacterial richness changed with the kinds of organic fertilizer and with tobacco development. The bacterial community structures of the soil were significant affected by applying organic fertilizers. On the level of phylum and genus,the dominant bacteria obviously changed with different organic fertilizers and chemical fertilizers. Especially, the bacterial richness of Candidatus was enhanced by applying organic fertilizers, while the bacteria of Rubrobacter and Nitrospira decreased compared with sole chemical fertilizer application. The analysis of KEGG metabolic pathways showed that the function and metabolism of soil bacteria changed significantly after applying organic fertilizers in tobacco fields. In conclusion, application of organic fertilizers improved soil bacterial polymorphisms and may achieve the effect of soil conservation in tobacco fields.