Effect of sublethal dosage of fenvalerate to growth and development of the silkworm,Bom-byx mori
In order to provide reference for choosing pesticides in controlling pests in agro-mulberry mixed planting areas,the acute toxicity and developmental toxicity of fenvalerate to silkworm were investigated by leaf dipping meth-od.The results of acute toxicity showed that the 96 h-LC50 for the 2nd instar larvae to fenvalerate was 0.251-0.570 mg·L-1,belonging to high and extreme level toxicity.The results of developmental toxicity showed that after the treatments at the sublethal dosages(0.062 8,0.020 9,0.006 98,0.002 33 and 0.000 775 mg·L-1)of fenvaler-ate,the development duration and body weight of molting larvae were affected,and the influence gradually became less abvious with instar.The rate of pupation and dead cocoons of 0.002 33 and 0.000 775 mg·L-1 fenvalerate treat-ment groups were significantly affected(P<0.05),which significantly affected the individual growth and develop-ment.The cocoon shell weight of 0.062 8,0.020 9 and0.006 98 mg·L-1 fenvalerate treatment groups were signifi-cantly lower than that of the control group(P<0.05).Results showed that fenvalerate had high acute and chronic toxic effects on silkworms.Therefore,when using fenvalerate in agro-mulberry mixed planting areas,mulberry pollu-tion from droplet drift or other agricultural activities should be avoided.
fenvalerateBombyx morisublethal effectgrowth and developmental toxicity
万方数据
维普
