Control Efficiency of Different Formulations of Emamectin Benzoate·Chlorpyrifos against Sogatella furcifera and Evaluation of Their Safety to Predatory Spiders in Rice Fields

The field test results showed that applying 25% emamectin benzoate· chlorpyrifos EW 1500~1800 mL/hm 2 had good control efficiency on Sogatella furcifera in rice field,among them 25% emamectin benzoate· chlorpyrifos EW 1500 mL/hm 2 had better control efficiency on Sogatella furcifera than 25% emamectin benzoate· chlorpyrifos EC 1500 mL/hm 2,but had significantly lower control efficiency than pymetrozine.One day after treatment,25% emamectin benzoate· chlorpyrifos EW 1500~1800 mL/hm 2 had a certain killing role to the major predatory spiders in rice field,but its killing rate(46.51%~56.60%) was less than that of 25% emamectin benzoate· chlorpyrifos EC 1500 mL/hm 2 and chlorpyrifos treatment.Fifteen days after spraying,25% emamectin benzoate· chlorpyrifos EW had no killing effect on the main spiders in paddy field.The dosage of 25% emamectin benzoate· chlorpyrifos EW for the control of Sogatella furcifera in rice should be more than 1800 mL/hm 2.