Effects of sulfoxaflor on greenhouse vegetable soil N2O emissions and its microbial driving mechanism

Abstract The wide application of pesticides ensures the safety of food production, but it also has a serious impact on soil ecosystem. Although sulfoxaflor as a pesticide has great potential for application due to its excellent insecticidal activity and low crossresistance, little is known about its soil environmental safety risks. In this study, the effects of sulfoxaflor on N 2 O emissions and microorganisms in greenhouse vegetable soils were studied by indoor simulation culture experiments. Dynamic changes of soil main inorganic N and N 2 O emission rate were tested, and the abundance and community of total bacteria and microorganisms related to N cycle were analyzed. The results indicated that soil microorganisms rapidly degraded sulfoxaflor, and the N 2 O emissions rate and ammonium nitrogen (NH 4 +- N) content significantly increased, while nitrate nitrogen (NO 3 - -N) content was significantly decreased. Sulfoxaflor significantly changed the abundance and community of total bacteria, nitrite reducing and nitrous oxide reducing bacteria, but had no significant effect on ammoxidation microorganisms. The N 2 O emission rate was positively correlated with gene abundance of denitrifying microorganisms. Under 65% soil maximum water holding capacity, sulfoxaflor may broke the dynamic balance of N 2 O production and consumption in the denitrification process, which caused a significant increase in N 2 O emission. Therefore, the application of sulfoxaflor had a certain effect on N cycling and utilization in greenhouse vegetable soil.