Differential neurosensory responses of adult Colorado potato beetle, Leptinotarsa decemlineata, to glycoalkaloids

Neurons from chemosensory hairs on the galeae of adult Colorado potato beet le (CPB), Leptinotarsa decemlineata (Say), were investigated for responses to glycoalkaloids of the family Solanaceae. While solanine and tomatine eli cited irregular firing by multiple neurons and bursting activity at I mM co ncentration in most sensory hairs, stimulation with leptine I resulted in c onsistently high-frequency, slowly adapting responses with a dose-dependent effect between 0.03 and 0.3 mM concentrations. Responses to a mixture of s olanine and leptine I suggested possible modification of the leptine I resp onse by other glycoalkaloids, resulting in reduced neural activity relative to leptine I alone. These results establish a method for specifically eval uating leptine I and other glycoalkaloids for effects on feeding behavior o f CPB and provide a sensory component for incorporating deterrent chemistry into biorational control methods for the CPB.