The Response Of Microbial Community To Petroleun Pollution And Planting Robinia Pseudoacacia In Diffirent Agricultural Soils

Soil is the base of agricultural production, when soil was contaminated by crude oil, the soil functions will decrease, the growth of crops and soil microbes suffer serious damages.Soil microbe is the main participants in soil formation, biogeochemical cycle and the degradation of pollutants, it is a important factor affecting soil ecological process. Study the response of agricultural soil microbial to oil pollution has an important significance for the exploration of ecosystem functions and promoting sustainable use of farmland soil. This study collected agricultural soil samples from 21 locations all over the country, agricultural soil were treated using four methods: water conservation, oil polluted, planting Robinia pseudoacacia, oil polluted+ planting Robinia pseudoacacia, and each treatment was cultivated in greenhouse 60 days, after 60 days using the strategy of 16 S rRNA Miseqpyrophosphate sequencing measure soil microbial community, using bioinformatics tools to campare the diversity and composition of the microbial community between treatments and analyze the differences of the microbial community between treatments, and to reveal the changes of agricultural soil microbial communities response to oil contaminated.At the same time captured the rhizobium from 21 agricultural soils by planting Robinia pseudoacacia to study the diversity of the Robinia rhizobia and the selection of the symbiotic rhizobium in oil contaminated soils. The main results were as follows:Through the pyrophosphate sequencing, 3,489,918 high-quality sequence obtained and6,698 OTUs from 105 soil samples, these OTUs distributed in 39 phylum, 120 class, 174 orders, 226 family, 260 genus. Proteobacteria, Actinobacteria, Acidobacteria and Chloroflexi are 4 main groups of bacterial, Candidatus Nitrososphaera(0.19%)is the main groups of archaea.The results of the impact of different treatment on soil microbial community showed each treatment had significant impact the alpha diversity and beta diversity of microbial community. After soils were contaminated by oil, the soil microbial community diversity decreased, and the community structure changed significantly. On the level of OTU, the compositions and abundances of each treatment was significantly different, the OTU numberin each treatments comparing with the number of original soil microbial OTU changed, the most enriched groups in oil polluted treatment and oil polluted+ planting Robinia pseudoacacia treatment can participate in oil degradation.Planting Robinia pseudoacacia in oil polluted soils and unpolluted soils,a total of 61 rhizobia were captured, the phylogenetic analysis of 16 S rDNA gene indicated they belonged to 4 genus Rhizobium, Shinella, Sinorhizobium and Mesorhizobium. Their nodA gene formed three groups and distributed in three genus including Mesorhizobium, Sinorhizobium and Rhizobium, nodC gene were close to Rhizobium leguminosaru, the phylogenetic analysis of nif H gene was similar to nodA gene. There is no significant differences in the selection of rhizobia by Robinia pseudoacacia between oil polluted treatment and unpolluted treatment, oil had no significant impact on rhizobial diversity from the root nodules of Robinia pseudoacacia.This study aimed at multiple locations of agricultural soils, the changes of microbial community response to oil pollution and plant cultivation revealed the impact of oil-plant on agricultural soils microbial community, it will provide basic clues of the response of agricultural soil microbial community after oil polluted and the changes of agricultural soil microbial community after planting.