The redox cycle of iron (Fe) is a key process in the biogeochemistry of paddy field soil. It has been recently remarked that Fe(II)-oxidizing bacteria belonging to the family Gallionellaceae (Gallionella-related FeOB) are one of the key players in the Fe(II) oxidation in the soil. The present study aimed to investigate the influence of alternate wetting and drying (AWD) irrigation for water-saving rice cultivation on the dynamics of the community of Gallionella-related FeOB in the paddy field soil over three seasons (wet-dry-wet seasons) of rice cultivation. The AWD irrigation brought about the reduction of Fe(II) contents in the soil, compared with the continuously flooding (CF) irrigation, especially in the last half of the rice cultivation period in the dry season. In contrast, a trend of higher copy number of 16S rRNA genes of Gallionella-related FeOB was observed in the last half of the rice cultivation period of the AWD paddy soil. As a result, a significant negative correlation was observed between the Fe(II) contents and the copy numbers of 16S rRNA genes. PCR-DGGE analysis of 16S rRNA genes of Gallionella-related FeOB showed that the band patterns were different between the CF and AWD paddy soils. Meanwhile, the results of clone library analysis indicated that differences in the taxonomic composition of Gallionella-related FeOB were not observed between the CF and AWD paddy soils, suggesting that Gallionella-related FeOB responded to the AWD water-saving irrigation on the individual strain levels. The potential of Fe(II)-oxidizing activity and its apparent contribution of the activity of Gallionella-related FeOB to the Fe(II) oxidation in the soil of the investigated field were estimated to be 2.4 × 10⁻³ to 1.7 × 10⁻¹ mg Fe(II) g⁻¹ dry soil day⁻¹ and 4.6%, respectively, based on the reported Fe(II) oxidation rates of cells. The present study showed that the fluctuation of the redox status of Fe caused by the repeated cycle of wetting and drying of the field brought about the changes in the community structure of Gallionella-related FeOB in the soil. Furthermore, it was suggested that Gallionella-related FeOB were certainly involved in the Fe(II)-oxidizing process in the AWD paddy field soil.

铁（Fe）的氧化还原循环是稻田土壤生物地球化学中的关键过程。据最近表示的Fe（II）氧化属于家庭细菌Gallionellaceae（嘉利翁氏菌-相关铁细菌）是中铁在土壤中（II）氧化的关键球员之一。本研究旨在调查节水水稻种植中的干湿交替灌溉对鸡只群落动态的影响水稻种植三个季节（干湿湿季节）下稻田土壤中的铁相关的FeOB。与连续淹水（CF）灌溉相比，AWD灌溉减少了土壤中的Fe（II）含量，尤其是在旱季水稻种植期的后半段。相反，在AWD稻田的水稻栽培期的后半期，观察到了与Gallionella相关的FeOB的16S rRNA基因拷贝数增加的趋势。结果，在Fe（II）含量和16S rRNA基因的拷贝数之间观察到显着的负相关。鸡痢疾16S rRNA基因的PCR-DGGE分析相关的FeOB表明，CF和AWD水稻土的带型不同。同时，克隆文库分析的结果表明，在CF和AWD水稻土之间未观察到与Gallionella相关的FeOB的分类学组成差异，这表明Gallionella相关的FeOB在单个菌株水平上对AWD节水灌溉有响应。的Fe（II）的电势-oxidizing活性和活性的其表观贡献嘉利翁氏菌-相关铁细菌到铁（II）中所研究的场的土壤氧化估计为2.4×10 ^-3〜1.7×10 ^{- 1}  mg Fe（II）g ^-1干燥土壤，第^-1天根据报告的细胞Fe（II）氧化速率分别为4.6％和4.6％。本研究表明，田间湿润和干燥的反复循环引起的铁氧化还原状态的波动导致了土壤中与金鸡病有关的FeOB的群落结构发生变化。此外，有人建议与鞭毛虫有关的FeOB确实参与了AWD稻田土壤中的Fe（II）氧化过程。