Effects of Extracts from Castor Plant Leaves against Spodoptera litura Fabricius Larva

[Objective] The aim was to understand effects of extracts from castor plant leaves against Spodoptera litura Fabricius larva to provide reference for bio-control of Spodoptera litura. [Method] The olfactory response of extracts from castor leaves at early fruit-setting stage,full fruit-setting stage and fruit pre-mature stage on Spodoptera litura were studied,and effects of the extracts on the feeding behavior of S. litura larvae and larval survival rate were also studied. [Result]The extracts from castor bean leaves had significant repellent effects on S. litura.The repellent rates of both 2nd and 5th larvae exceeded 69%. Compared with the control,larvae treated cabbage food intake decreased by42. 46%- 47. 08%,the number of feeding activity and feeding time was reduced,and the survival rate of larvae was decreased by 38. 10%- 52. 39%. The repellent intension of the extracts of the three growth stages to S. litura were pre-mature period full fruiting period early fruit-setting period. But,there was no significant difference between S. litura larvae's food consumption and the survival rate. [Conclusion]The castor bean leaves have good repellent and antibiosis effects on S. litura.