南京小龙山钾矿区植物根际可培养细菌的遗传多样性分析

摘要:【目的】矿区优势植物可培养细菌生物多样性研究将有助于了解植物根际细菌与矿物,植物根系相互作用及对矿物风化和土壤形成的重要影响。【方法】采用纯培养法分离南京小龙山废钾矿区野生植物野塘蒿,千金子和栽培植物甘薯根内与根周围土壤的可培养细菌, 通过16S rDNA限制性酶切多态性分析(amplified rDNA restriction analysis, ARDRA)和16S rDNA序列分析研究了可培养细菌的多样性。【结果】分离纯化到60株具不同菌落形态的可培养细菌, 在60%相似水平上可分为18个OTU. 19株代表菌株分别属于3个门, 10个科, 11个属。多数菌株属于变形菌门(α-proteobacteria, 4株, 21.1%; β-proteobacteria, 2株, 10.5%; γ-proteobacteria, 6株, 31.6%)。假单胞菌属(Pseudomonas), 泛菌属(Pantoea)和根瘤菌属(Rhizobium)为优势种群。【结论】小龙山废矿区优势植物根围具有丰富的微生物种群多样性。

Genetic diversity of cultivable bacteria of dominant plants in a potassium mine tailing of Nanjing

Abstract: Objective] Plant rhizosphere bacteria play an important role in biogeochemical cycles. Microbial diversity of cultivable bacteria from soil-plant-mineral system in a mine tailing was assessed. Methods] Cultivable bacteria were isolated by plating and screening from plant root, rhizosphere and bulk soils of predominant plants in a mine tailing of Nanjing, Jiangsu Province. Phylogenetic analyse based on 16S rDNA sequence comparisons and amplified rDNA restriction analysis of isolates were investigated. Results] In total, 60 pure cultures were isolated; they could be grouped into 18 different operational taxonomic units (OTU) at the similarity level of 60%. Nineteen bacterial strains belonged to eleven genera (Rhizobium, Pseudomonas, Pantoea, Arthrobacter, Microbacterium, Bacillus, Paenibacillus, Acinetobacter, Sphingomonas, Kocuria, Mitsuaria) of three major phylogenetic groups (Proteobacteria, Actinobacteria, Firmicutes). Rhizobium, Pseudomonas and Pantoea were the dominant groups. Conclusion] Different cultivable bacteria inhabited in roots and soils of dominant plants in the mine tailing. They might play a certain role in the soil-plant-mineral environment.