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模拟水稻土淹水过程,采用Real-time PCR技术测度了不同水稻土中地杆菌(Geobacteraceae spp.)和厌氧粘细菌(Anaeromyxobacter spp.)在不同淹水时期16S rDNA拷贝数的变化,比较了地杆菌和厌氧粘细菌丰度与培养过程中微生物Fe(Ⅲ)还原的关系。结果表明,在4类稻作区采集的水稻土样品中,Fe(Ⅲ)还原潜势有明显的区别,表现出由北向南逐渐降低的趋势。从淹水12 h的地杆菌和厌氧粘细菌拷贝数变化看出,采自浙江和天津的水稻土样品对淹水过程具有高度敏感性,而采自吉林和广西的水稻土样品对淹水响应不敏感。在17 d的短期淹水培养中,地杆菌丰度明显高于厌氧粘细菌,表明地杆菌对水稻土中铁还原的贡献大于厌氧粘细菌。地杆菌和厌氧粘细菌拷贝数总体上表现出在11 d时达到峰值,17 d时显著下降。吉林水稻土中地杆菌丰度在5 d时达到38.3%,与其最大铁还原速率到达时间(TVmax)为4.07 d相对应,表明地杆菌对其铁还原过程具有重要贡献。四川水稻土中地杆菌和厌氧粘细菌丰度均较低,暗示其他兼性铁还原菌对其铁还原的作用值得重视。
The changes of 16S rDNA copy number of Geobacteraceae spp. And Anaeromyxobacter spp. In different flooding periods were measured by Real-time PCR. Relationship between Abundance of Bacteroides and Anaerobic Bacterium and Fe (Ⅲ) Reduction during Cultivation. The results showed that there was a clear difference in the reduction potential of Fe (Ⅲ) in paddy soils collected from four types of paddy fields, showing a trend of decreasing gradually from north to south. The results showed that the paddy soil samples collected from Zhejiang and Tianjin were highly sensitive to the flooding process. However, the paddy soil samples collected from Jilin and Guangxi were not sensitive to flooding Response is not sensitive. In 17 days of short-term flooding culture, the abundance of geobacteria was significantly higher than that of anaerobic myxobacteria, suggesting that the contribution of geobacillus to iron reduction in paddy soil was greater than that of anaerobic myxobacteria. The numbers of copies of Bacteroides and anaerobic myxobacteria generally peaked at 11 days and decreased significantly at 17 days. The geobacillus abundance in paddy soil of Jilin Province reached 38.3% at 5 days, corresponding to its maximum TVR of 4.07 days, which indicated that Geobacillus had an important contribution to its iron reduction process. The abundance of Bacillus subtilis and anaerobic myxobacteria in paddy soils in Sichuan Province are low, suggesting that the role of other facultative iron-reducing bacteria in their iron reduction deserves attention.