新烟碱类手性农药环氧虫啶在不同种植体系下的环境行为与归趋

The hazardous environmental impacts of the traditional neonicotinoid pesticides have been continuously reported, and it’s been the global scientific attention to explore their substitutes. Cycloxaprid is a novel neonicotinoid pesticide initiatively developed by China, and is considered to be one of the most promising candidate alternatives for the traditional neonicotinoid pesticides. However, the environmental behavior and fate of cycloxaprid in different planting system remains poorly understood. In this project, the stereoselective environmental behavior and fate of 14C-cycloxaprid in typical planting system will be characterized by combining techniques of isotopic tracing, instrumental analysis, high-throughput sequencing and bioinformatics methods. The main research objective of this project is to investigate the uptake, transformation, directional accumulation and metabolism of 14C-cycloxaprid enantiomers in plants, the degradation and residual properties in soils and in continuous cropping system, and the subsequent transformation in soils and directional accumulation in the plants. The effects of cycloxaprid on soil microbial diversity will also be studied to elucidate the possible interaction mechanisms between the microorganisms and the cycloxaprid degradation and transformation in the soil. The study aims to elaborate environmental behavior and fate of cycloxaprid from the perspective of its enantiomers in different planting systems, and clarify the directional accumulation, especially the plant organs in relation to the trophic cascade of non-target organisms, and metabolic characteristics in different plants. The obtained results will provide important implications for a more accurate prediction about the risk assessment of this novel neonicotinoid insecticide, which will be helpful for guiding its rational use and making the referred environmental criteria more reasonably. The project is going to provide important scientific and practical significances for securing the ecological environment safety and human health.

新烟碱类传统农药对环境的负面效应备受关注。探寻该类农药替代品是全球热点之一。环氧虫啶是我国创制的该类农药候选替代品，但目前对其环境行为与归趋的认识很有限。项目以14C标记环氧虫啶为对象，综合运用同位素示踪、仪器分析和高通量测序等技术，围绕不同种植体系，从对映体层面出发，着重研究环氧虫啶对映体“在植物中的吸收运转、定向积累与代谢规律”、“在土壤中的降解与残留转归特性”，“连作体系下土壤中环氧虫啶残留的后续转化及其在后茬中的定向积累”以及“对土壤微生物多样性的影响”，并探讨微生物与土壤中环氧虫啶降解转化间可能的互作机理。旨在从手性角度阐明不同种植体系下环氧虫啶的环境行为与归趋，明确其在不同植物中的定向积累（尤其是与非靶标生物营养级联有关的植物器官的残留规律）与代谢特征，为更客观评估与科学认识环氧虫啶的环境安全性，指导该药合理使用提供理论依据。项目对保障生态环境和人类健康有重要的科学和现实意义。

新烟碱类传统农药吡虫啉等对环境造成的负面效应备受关注。探究高效且环境友好的该类农药替代品，已成为全球迫切需要解决的科学技术问题之一。环氧虫啶是我国具有自主知识产权且应用前景广阔的新烟碱类杀虫剂候选替代品。然而，人们对环氧虫啶环境行为与归趋的认识仍很有限。本项目以14C标记环氧虫啶对映体（14C标记化合物I和14C标记化合物II）为示踪剂，发挥放射性同位素示踪技术具有的痕量精准和溯源追踪之独特优势，并综合运用HPLC-FSA和HPLC-QTOF-MS等先进仪器分析技术，以及高通量测序技术和生物信息学方法，系统研究了“环氧虫啶对映体在植物中的吸收运转、定向积累与代谢规律”、“环氧虫啶对映体在土壤中的降解与残留转归特性”、“连作体系下土壤中环氧虫啶残留的后续转化及其在后茬中的定向积累”以及“环氧虫啶对映体对土壤微生物多样性的影响”，并探讨微生物与土壤中环氧虫啶降解转化之间可能的互作机理。本项目从手性角度阐明了不同种植体系下环氧虫啶的环境行为与归趋，明确了其在不同植物中的定向积累（尤其是与蜜蜂等非靶标生物营养级联有关的植物器官的残留规律）与代谢特征，以及不同种植体系下环氧虫啶在土壤中的降解与残留转归特性，为客观评估环氧虫啶的环境安全性和指导该药的科学合理使用提供理论依据和技术支撑。