Fig. 1.

Behavioral responses in Bombyx mori and Helicoverpa armigera larvae. Bombyx mori behavioral responses to salicin (a) and to caffeine (b). Helicoverpa armigera behavioral response to salicin (c) and to caffeine (d). Curves indicate the mean feeding inhibition (N = 30). Curves were fitted with a variable slope nonlinear fit. Bars represent standard errors of the mean. The orange and green (shaded) areas on the graphs represent the range of concentrations encountered in rich natural plant sources of salicin and caffeine, respectively