熏蒸剂氯化苦胁迫下对逃逸蚯蚓的毒性效应及机制研究

Soil fumigant chloropicrin (Pic) is widely used to control soil-borne pests due to the broad-spectrum, economically efficient, and excellent fumigation effect. However, chloropicrin fumigation poses threats to the non-target organisms due to the high toxicity. Earthworm is a beneficial and ecologically important bio-indicator soil organism. During chloropicrin fumigation, the escape behaviour of earthworms was obviously observed and the survived earthworms were the main source for the population recovery. However, there is little information on toxic effect, population recovery and toxic mechanism of fumigant chloropicrin stress on escaped earthworms. Therefore, in this project, toxic effect of chloropicrin stress on growth, development, reproduction and heredity of the survived earthworm (Eisenia fetida) will be studied by simulating field chloropicrin fumigation. In order to elucidate the toxic mechanism, transcriptome and proteome sequencing analysis will be conducted and followed by characterization of key genes with RNAi technology etc. Finally, the potential biomarkers of toxic effect assessments will be explored for chloropicrin risk assessment. Results of this project will provide the theoretical basis for risk assessments of fumigant chloropicrin on soil ecosystem.

氯化苦是一种广谱、经济且效果显著的土壤熏蒸剂，在农业生产上被广泛使用，但其毒性高，对非靶标生物造成严重威胁。蚯蚓是土壤中一种重要有益生物，也是土壤环境的指示生物。田间应用氯化苦时，蚯蚓逃逸现象明显，存活蚯蚓成为熏蒸区域种群恢复的重要来源。然而氯化苦对逃逸存活蚯蚓是否存在毒性、影响种群恢复以及机制鲜有报道。因此，本项目拟通过模拟田间氯化苦施用场景，研究氯化苦熏蒸胁迫下对逃逸蚯蚓生长、发育、繁殖和遗传的毒性，评价对蚯蚓种群恢复的影响；通过转录组和蛋白质组相关联分析，挖掘毒性效应相关的候选基因；采用RNA干扰等分子、生化方法，对差异表达关键基因的功能进行验证，揭示氯化苦对蚯蚓毒性及种群恢复的影响机制；分析毒性与关键基因表达的相关性，发现氯化苦生态毒性评价潜在生物标志物。研究结果将为科学合理地评价氯化苦生态安全风险提供理论依据。

项目以明确氯化苦对蚯蚓的毒性效应，开展土壤熏蒸剂的生态毒理评价和风险评估为主要研究目标，主要开展了以下三个方面的研究内容：1）易挥发化学农药对赤子爱胜蚯蚓的急性毒性标准评价方法建立和完善；2）氯化苦等常见土壤熏蒸剂对赤子爱胜蚯蚓逃逸行为规律及其急性毒性效应研究；3）氯化苦等常见土壤熏蒸剂对赤子爱胜蚯蚓的初级急性环境风险评估。取得的主要研究结果为：1）通过密闭干燥器人工土壤法建立并完善了易挥发化学农药对赤子爱胜蚯蚓的急性毒性评价方法，牵头起草标准草稿，并组织完成了标准方法验证，形成了农业行业标准报批稿；2）基于建立的标准方法，系统评价并明确了氯化苦等常见土壤熏蒸剂对赤子爱胜蚯蚓逃逸行为规律及其急性毒性效应差异；3）采用PECsoil-SFO-China模型评估了氯化苦等常见土壤熏蒸剂对赤子爱胜蚯蚓的初级急性环境风险，并为高级环境风险评估提供了数据参考。目前项目已经发表标注项目资助的论文11篇（第1标注3篇，第2标注8篇），其中SCI论文5篇。本项目预算执行和经费开支符合规定，项目总费用32.4000万元，结余6.8123万元，项目经费结余占比21.03%，剩余经费计划用于本项目研究的后续支出。