The Toxicity Analysis Of Diamide Insecticides To Apis Mellifera

Honey bee(Apis mellifera)is an important pollinating economic insect,which can help plant pollination and improve crop yield and quality.The pollination of honey bee plays an important role in protecting species diversity and the ecological environment.The modern agricultural production cannot be separated from the use of insecticides.In the process of using the insecticides,the bees have a lot of accesses to pesticides.The diamide insecticide is a new class of insecticides which was developed in recent years.To better protect bees,it is necessary to study the toxic effect of diamide insecticides to A.mellifera.In this study,three kinds of diamide insecticides(20%flubendiamide water dispersible granules(WDG),20%chlorantraniliprole suspension and 20%cyantraniliprole suspension)were selected to analyze their acute toxicity to bee adults and larvae.The activities of carboxylesterase(CarEs)and glutathione S-transferase(GSTs)were measured after the treatment of the three insecticides.Under the semi-field condition,the effects of three insecticides on the pollination amount,the death rate and the flight intensity of honey bee were studied.1.The acute oral toxicities(LC50)of 20%flubendiamide WDG,chlorantraniliprole suspension and cyantraniliprole suspension to the bee adults were 18.397×103,11.478×103,2.288 × 10-3 mg/L,and the toxicity levels were low toxicity,low toxicity and high toxicity,respectively.The acute toxicities(LD50)of the three insecticides to the bees were>100,>100,3.65 × 10-2 μg/bee,respectively,and the three insecticides have low,low and high toxicity.2.The medium lethal doses(LD50)of flubendiamide WDG,chlorantraniliprole suspension and cyantraniliprole suspension to the bee larvae were>100,5.565,0.212μg/larva,respectively.3.The activities of CarEs after the treatment of flubendiamide WDG and cyantraniliprole suspension were higher than that of the control,which means the activities of CarEs could be induced by flubendiamide WDG and cyantraniliprole suspension,but the activities of CarEs were inhibited by chlorantraniliprole suspension.The GSTs activities were significantly induced by these insecticides.The GSTs activities after the treatment of the three insecticides showed significantly higher than that of the control.4.Under the condition of semi-field,the pollination,the death amount and the flight frequency could be affected after the treatment of three insecticides,when the influence will be eliminated with the increase of the application time.The number of death in honey bee 2-6 day after the flubendiamide WDG treatment was significantly different to that of the control,and it recovered at the seventh day.After the treatment of chlorantraniliprole suspension,the bees were rapidly poisoned and had a large number of death,while the number of death at 7 days had not difference between the treatment and the control.The effect of cyantraniliprole on the survival of bees was not obvious,and the mortality rate was significantly higher than that of the control only at the fourth day after the treatment.The results showed that the toxicity of flubendiamide WDG,chlorantraniliprole suspension and cyantraniliprole suspension to bees were low,low and high,respectively.The response of detoxification enzymes to insecticides in the bees also reflected the toxicity difference of the three insecticides.The results of semi-field experiments showed the effect of three insecticides on the behavior and survival of bees.The present study will provide a theoretical basis for the rational use of diamide insecticides and better protection of bees.