State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, PR China.
Jinhua Academy of Agricultural Sciences, Jinhua 321000, PR China.
Ecotoxicol Environ Saf. 2023 Mar 15;253:114658. doi: 10.1016/j.ecoenv.2023.114658. Epub 2023 Feb 14.
Pesticide residues have serious environmental impacts on rice-based ecosystems. In rice fields, Chironomus kiiensis and Chironomus javanus provide alternative food sources to predatory natural enemies of rice insect pests, especially when pests are low. Chlorantraniliprole is a substitute for older classes of insecticides and has been used extensively to control rice pests. To determine the ecological risks of chlorantraniliprole in rice fields, we evaluated its toxic effects on certain growth, biochemical and molecular parameters in these two chironomids. The toxicity tests were performed by exposing third-instar larvae to a range of concentrations of chlorantraniliprole. LC values at 24 h, 48 h, and 10 days showed that chlorantraniliprole was more toxic to C. javanus than to C. kiiensis. Chlorantraniliprole significantly prolonged the larval growth duration, inhibited pupation and emergence, and decreased egg numbers of C. kiiensis and C. javanus at sublethal dosages (LC = 1.50 mg/L and LC = 3.00 mg/L for C. kiiensis; LC = 0.25 mg/L and LC = 0.50 mg/L for C. javanus). Sublethal exposure to chlorantraniliprole significantly decreased the activity of the detoxification enzymes carboxylesterase (CarE) and glutathione S-transferases (GSTs) in both C. kiiensis and C. javanus. Sublethal exposure to chlorantraniliprole also markedly inhibited the activity of the antioxidant enzyme peroxidase (POD) in C. kiiensis and POD and catalase (CAT) in C. javanus. Expression levels of 12 genes revealed that detoxification and antioxidant abilities were affected by sublethal exposures to chlorantraniliprole. There were significant changes in the expression levels of seven genes (CarE6, CYP9AU1, CYP6FV2, GSTo1, GSTs1, GSTd2, and POD) in C. kiiensis and ten genes (CarE6, CYP9AU1, CYP6FV2, GSTo1, GSTs1, GSTd2, GSTu1, GSTu2, CAT, and POD) in C. javanus. These results provide a comprehensive overview of the differences in chlorantraniliprole toxicity to chironomids, indicating that C. javanus is more susceptible and suitable as an indicator for ecological risk assessment in rice ecosystems.
农药残留对基于水稻的生态系统具有严重的环境影响。在稻田中，摇蚊科的库蚊属和沼蚊属为水稻害虫的捕食性天敌提供了替代食物来源，尤其是在害虫数量较低时。氯虫苯甲酰胺是替代旧类杀虫剂的一种药剂，已被广泛用于防治水稻害虫。为了确定氯虫苯甲酰胺在稻田中的生态风险，我们评估了其对这两种摇蚊某些生长、生化和分子参数的毒性影响。通过将三龄幼虫暴露于一系列氯虫苯甲酰胺浓度下进行毒性测试。24 小时、48 小时和 10 天的 LC 值表明，氯虫苯甲酰胺对沼蚊的毒性比对库蚊更强。亚致死剂量下，氯虫苯甲酰胺显著延长了幼虫的生长时间，抑制了蛹化和羽化，并降低了库蚊和沼蚊的产卵数（LC = 1.50 毫克/升和 LC = 3.00 毫克/升用于库蚊；LC = 0.25 毫克/升和 LC = 0.50 毫克/升用于沼蚊）。亚致死浓度的氯虫苯甲酰胺暴露显著降低了库蚊和沼蚊中羧酸酯酶（CarE）和谷胱甘肽 S-转移酶（GSTs）的解毒酶活性。亚致死浓度的氯虫苯甲酰胺暴露还显著抑制了库蚊中过氧化物酶（POD）和沼蚊中 POD 和过氧化氢酶（CAT）的抗氧化酶活性。12 个基因的表达水平表明，解毒和抗氧化能力受到氯虫苯甲酰胺亚致死暴露的影响。库蚊中有 7 个基因（CarE6、CYP9AU1、CYP6FV2、GSTo1、GSTs1、GSTd2 和 POD）和沼蚊中有 10 个基因（CarE6、CYP9AU1、CYP6FV2、GSTo1、GSTs1、GSTd2、GSTu1、GSTu2、CAT 和 POD）的表达水平发生了显著变化。这些结果全面概述了氯虫苯甲酰胺对摇蚊的毒性差异，表明沼蚊更易受影响，适合作为水稻生态系统生态风险评估的指标。
