Hunan Soil and Fertilizer Institute, Changsha, China.
J Appl Microbiol. 2022 Feb;132(2):1307-1318. doi: 10.1111/jam.15289. Epub 2021 Sep 14.
The potential nitrification activity (PNA), population size and community composition of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in paddy soil from a short-term (5 years) tillage field experiment conducted at tillering stage of late rice were investigated using the shaken slurry method and quantitative real-time polymerase chain reaction.
The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue returning (NT) and rotary tillage with all crop residues removed as a control (RTO). The results showed that PNA in paddy soil of CT, RT and NT treatments was higher than that of RTO treatment, and the abundance of AOA and AOB was much higher in paddy soil of CT, RT and NT treatments than RTO treatment. Meanwhile, PNA and the abundance of AOB and AOA in paddy soil were greatly enhanced by combined application of tillage and crop residue, whereas PNA and the abundance of AOB and AOA in paddy soil were decreased by combined application of no-tillage and crop residue. Moreover, PNA was closely correlated with the abundance and community structure of AOB rather than AOA. The results also showed that PNA and the population sizes of AOB and AOA in crop incorporation treatments were higher than that of crop residue removed treatment. Cluster and redundancy analyses indicated that crop residue effect played a more important role in shaping AOA community structure compared to short-term tillage management.
The results indicated that AOB rather than AOA functionally dominated ammonia oxidation in the double-cropping rice paddy soil, the activities of AOB and AOA were increased and the community structure was also changed under the combination of conventional tillage, rotary tillage and crop residue condition.
The activity and community structure of AOB and AOA, which were affected by the combination of tillage and crop residue managements, play an important role in cycling of nitrogen.
采用摇瓶法和实时定量聚合酶链反应（qPCR）技术，研究了短期（5 年）水稻分蘖期耕层试验中稻田土壤潜在硝化活性（PNA）、氨氧化细菌（AOB）和氨氧化古菌（AOA）的种群大小和群落组成。
试验包括 4 种耕作处理：常规耕作并施入作物残茬（CT）、旋耕并施入作物残茬（RT）、免耕并施入作物残茬（NT）和不耕作并移除所有作物残茬作为对照（RTO）。结果表明，CT、RT 和 NT 处理的稻田土壤 PNA 高于 RTO 处理，CT、RT 和 NT 处理的稻田土壤 AOA 和 AOB 丰度明显高于 RTO 处理。同时，耕作和作物残茬的联合应用极大地增强了稻田土壤的 PNA 和 AOB 和 AOA 的丰度，而免耕和作物残茬的联合应用则降低了稻田土壤的 PNA 和 AOB 和 AOA 的丰度。此外，PNA 与 AOB 的丰度和群落结构密切相关，而与 AOA 关系不大。结果还表明，与去除作物残茬处理相比，施入作物残茬处理的 PNA 及其 AOB 和 AOA 种群丰度更高。聚类和冗余分析表明，与短期耕作管理相比，作物残茬效应在塑造 AOA 群落结构方面发挥了更重要的作用。
结果表明，在双季稻田土壤中，AOB 而非 AOA 功能上主导了氨氧化作用，在常规耕作、旋耕和作物残茬条件的结合下，AOB 和 AOA 的活性增加，群落结构也发生了变化。
受耕作和作物残茬管理组合影响的 AOB 和 AOA 的活性和群落结构在氮循环中起着重要作用。
