Differential Responses of Nitrifier and Denitrifier to Dicyandiamide in Short- and Long-Term Intensive Vegetable Cultivation Soils

作     者：LIU Yi YANG Yang QIN Hong-ling ZHU Yi-jun WEI Wen-xue 

作者机构：Key Laboratory of Agro-Ecological Processes in Subtropical Regions and Taoyuan Station of Agro-Ecology ResearchInstitute of Subtropical Agriculture Chinese Academy of Sciences Tianjin Land & Resources & Housing Management Research Centre 

出 版 物：《Journal of Integrative Agriculture》 (农业科学学报（英文版）)

年 卷 期：2014年第13卷第5期

页      面：1090-1098页

核心收录：

学科分类：09[农学] 0902[农学-园艺学] 090202[农学-蔬菜学] 

基　　金：financially supported by the National Natural Science Foundation of China (41071181, 41090282) the Chinese Academy of Sciences (KZCX2-YW-T07) 

主　　题：DCD amoA nirK vegetable soil 

摘      要：Nitrification inhibitors, such as dicyandiamide （DCD）, have been shown to decrease leaching from urea- and ammoniumbased fertilizers in agricultural soils. The effect of nitrification inhibitors on nitrifier and denitrifier in short- and long-term intensive vegetable cultivation soils was poorly understood. In this study, the pot trial was conducted to investigate the differential responses of nitrifier （amoA-containing bacteria） and denitrifier （nirK-containing bacteria） to DCD in short-（soil S） and long-term （soil L） intensive vegetable cultivation soils. Quantitative polymerase chain reaction （qPCR） and terminal restriction fragment length polymorphism （T-RFLP） were employed to detect the abundance and composition of amoA- and nirK-containing communities. The results indicated that application of DCD led to a consistently higher NH4＋-N concentration during the whole incubation in soil L, while it was quickly decreased in soil S after 21 days. Furthermore, DCD induced more severe decrease of the abundance of amoA-containing bacteria in soil L than in soil S. However, the abundance of the nirK- containing community was not significantly affected by DCD in both soils. Long-term vegetable cultivation resulted in a super-dominant amoA-containing bacteria group and less divergence in soil L compared with soil S, and DCD did not cause obvious shifts of the composition of ammonia-oxidising bacteria （AOB）. On the contrary, both amoA- and nirK-containing bacterial compositions were influenced by DCD in soil S. The results suggested that long-term intensive vegetable cultivation with heavy nitrogen fertilization resulted in significant shifts of AOB community, and this community was sensitive to DCD, but denitrifiers were not clearly affected by DCD.