关键词: 连作, 植烟土壤, 微生物群落结构, 真菌, 细菌

Abstract: In order to determine the effect of different continuous cropping years on microbial community structure in tobacco-planting soil, the paper selected typical tobacco-planting regions, collected soil samples with different continuous cropping years, and analyzed differences between bacteria and fungi community structure in tobacco-planting soil with different continuous cropping years by high-throughput sequencing technology. Results showed that the OTUs numbers of bacterial species in tobacco-planting soil for one year continuous cropping was the most, and that of fungal species for 4 years continuous cropping was the maximum. The bacteria ratio of Proteobacteria were the highest in soil with years continuous cropping. The proportion of Actinobacteria and Crenarchaeota in continuouse cropping soil showed a certain increasing trend, and at the same time, differences between soil bacteria community became large. The ratio of soil fungi were mainly Ascomycota. The proportion of Zygomycota in tobacco-planting soil fungi showed an increasing trend with the process of continuous cropping years. The fungal community composition in tobacco-planting soil for 2 and 4 years continuous cropping had certain similarity. In conclusion, continuous tobacco cropping decreased the diversity of soil bacteria and increased the diversity of fungi. Great changes had taken place in the structure of bacteria and fungi communities in tobacco-planting soil for 4 years continuous cropping.

Key words: continuous cropping, tobacco-planting soil, microbial community structure, fungi, bacteria