Effects Of Sulfoxaflor On The Health Of Worker Bees And The Quality Of Reared Queens In Honeybee (Apis Mellifera Ligustica)

Although pesticides can control pests and help improve agricultural production,their negative impact on pollinators has been significant.Bees are one of the most important pollinators in the environment.The toxic effects of environmental pesticides will not only affect the health of bee colonies,but also affect the agricultural industry closely related to bees pollination.Sulfoxaflor is a new insecticide,but there are few studies on its toxic effects on Apis mellifera.Insufficient data will affect the rational application of Sulfoxaflor.Misuse of pesticides can have a more serious impact on the environment.In this study,Apis mellifera were used as test subjects.First,the acute oral toxicity of Sulfoxaflor to bees was determined.We then investigated the effects of sublethal doses of Sulfoxaflor on the expression of immune,memory and detoxification related genes in worker bees and the quality of queen cultivation.The specific results are as follows:（1）The oral acute toxicity of Sulfoxaflor to Apis mellifera was determined by feeding tube method.The results showed that half of the lethal dose LD₅₀ for Apis mellifera was 0.099μg/bee.（2）After treatment with 1/10 LD₅₀ and 1/2 LD₅₀ doses of Sulfoxaflor nitrile for 24 hoursand 48 hours,fluorescence quantitative PCR was used to detect the body immune（Abaecin,Hymenoptaecin,Defensin,Apidaecin）,memory（Pka,Nmdar1,Glu RA）and detoxification（CYP9Q1,CYP9Q2,CYP9Q3,CYP6AS5,CYP9S1,CYP4G11）related gene expression changes of worker bees.The results showed that after 24 hours of treatment with Sulfoxaflor,1/10 LD50 dose treatment can significantly inhibit Abaecin,Hymenoptaecin,Defensin,Apidaecin,Nmdar1,Glu RA,CYP9Q1,CYP9Q2,CYP6AS5,CYP9S1 and CYP4G11expression（P<0.05）;And 1/2 LD50 dose treatment Hymenoptaecin,Apidaecin,Pka,Glu RA,CYP6AS5 and CYP9S1 expression was significant inhibition（P<0.05）,the expression levels of Abaecin,Defensin and CYP6AS5 were significantly up-regulated（P<0.05）.The expression of Abaecin was significantly inhibited by 1/10 LD₅₀ dose after 48 h treatment with fluidinamide（P<0.05）,the expression levels of Apidaecin,CYP6AS5 and CYP4G11were significantly up-regulated（P<0.05）.1/2 LD₅₀ dose treatment significantly inhibited the expression of Abaecin and Defensin（P<0.05）,while Apidaecin,Hymenoptaecin,Pka,Nmdar1,Glu RA,CYP9Q2,CYP9Q3,CYP6AS5 and CYP4G11 expression level rise significantly（P<0.05）.（3）Queen bee larvae were fed with a sublethal dose of Sulfoxaflor.When the queen left the hive,the sealing rate,emergence rate,total weight and head weight of the queen were calculated.Fluorescence quantitative PCR was used to detect the expression changes of antioxidant genes（Gstd1,Cat,Sod1,Sod2）,developmental related genes（Hex110,Hex71b,Vg）and apoptotic genes（Arr-1,Caspase-1）in queen bee ovary.The results showed that the emergence rate of queen bee could be significantly reduced by 0.1μg/bee dose of Sulfoxaflor（P<0.05）.Queen bee head weight was significantly reduced by 0.05μg/bee and 0.1μg/bee dose（P<0.05）.0.01μg/bee dose significantly inhibited the expression of Cat,Sod1 and Sod2,and induced the up-regulation of Gstd1（P<0.05）.0.05μg/bee and 0.1μg/bee dose showed significant inhibitory effects on the expression of Gstd1,Cat,Sod1 and Sod2（P<0.05）.0.01μg/bee、0.05μg/bee and 0.1μg/bee dose respectively significantly inhibited the expression of Hex110,Hex71b,Vg,Arr-1 and Caspase-1（P<0.05）.The half of the lethal dose LD50 for Apis mellifera was 0.099μg/bee.Belong to the high toxic.Sulfoxaflor affects the immunity and memory of Apis mellifera workers.The CYP9Q2,CYP9Q3,CYP6AS5 and CYP4G11 in Apis mellifera worker bees have detoxification effect on Sulfoxaflor.Sulfoxaflor can affect the breeding quality of new queen bee and impair the antioxidant function,development and apoptosis related function of ovary of queen bee.