Abstract
Chlordimeform and 4 natural antifeedants were assayed by the leaf-disc method for antifeeding activity in starved and nonstarved 5th instar larvae of the tobacco cutworm, S. litura. A relationship between the concentration of the antifeedants and the antifeeding ratio was found. The order of decreasing effectiveness within AC50 [median antifeeding concentration] values was as follows: clerodin .**GRAPHIC**. clerodendrin-B .**GRAPHIC**. caryoptin .**GRAPHIC**. clerodendrin-A > chlordimeform. The larvae showed varying symptoms in their feeding behavior against treated discs.