六种新烟碱类杀虫剂对凹唇壁蜂的毒性及风险评估

Toxicity and hazard assessment of six neonicotinoid insecticides on Osmia excavata (Hymenoptera:Megachilidae)

【目的】为评价新烟碱类杀虫剂对凹唇壁蜂Osmia excavata的毒性和风险性。【方法】分别采用饲喂法和接触法测定了啶虫脒、噻虫嗪、氟啶虫胺腈、吡虫啉、噻虫胺、呋虫胺6种新烟碱类杀虫剂对凹唇壁蜂雌成蜂的24 h和48 h的急性经口和接触毒性。并依据农药对蜜蜂生态风险的危害熵值(hazard quotient,HQ)评估其对凹唇壁蜂的风险性。【结果】经口毒性测定中,氟啶虫胺腈对凹唇壁蜂雌蜂毒性最高,噻虫嗪毒性最低;接触毒性测定中,噻虫胺对凹唇壁蜂雌蜂毒性最高,氟啶虫胺腈毒性最低。啶虫脒、噻虫嗪、吡虫啉对凹唇壁蜂表现为中等风险;噻虫胺经对凹唇壁蜂表现为高风险。氟啶虫胺腈和呋虫胺经接触途径表现为中等风险,而经口途径表现为高风险。【结论】本研究所选的6种新烟碱类杀虫剂对凹唇壁蜂雌成蜂的毒性均为高毒。在果园中应尽量避免使用噻虫胺、氟啶虫胺腈及呋虫胺,在植物花期谨慎使用啶虫脒、噻虫嗪、吡虫啉等新烟碱类杀虫剂。

【Aim】This study aims to assess the toxicity and hazard of six neonicotinoid insecticides to Osmia excavata.【Methods】The acute oral and contact toxicities of six neonicotinoid insecticides,i.e.,acetamiprid,thiamethoxam,sulfoxaflor,imidacloprid,clothianidin and dinotefuran,to the female adults of O.excavata at 24 h and 48 h after treatment were measured by feeding application and topical application methods,respectively.The risk of insecticides to O.excavata was assessed based on the hazard quotient(HQ)values of the ecological risk of insecticides to bees.【Results】In oral toxicity assay,sulfoxaflor showed the highest toxicity to the female adults of O.excavata while thiamethoxam showed the lowest toxicity.In contact toxicity assay,clothianidin showed the highest toxicity to the female adults of O.excavata,while sulfoxaflor showed the lowest toxicity.Acetamiprid,thiamethoxam and imidacloprid presented medium risk to O.excavata,while clothianidin presented high risk.And sulfoxaflor and dinotefuran presented medium risk to O.excavata by contact but high risk by oral exposure.【Conclusion】The six neonicotinoid insecticides assessed in this study present high risk to the female adults of O.excavata.It should be cautious to use acetamiprid,thiamethoxam and imidacloprid during florescence,and the use of clothianidin,sulfoxaflor and dinotefuran should be avoided in the orchard.