Experience-based behavioral and chemosensory changes in the generalist insect herbivore Helicoverpa armigera exposed to two deterrent plant chemicals.
Behavioral and electrophysiological responses of larvae of the polyphagous moth species Helicoverpa armigera to two plant-derived allelochemicals were studied, both in larvae that had been reared on a diet devoid of these compounds and in larvae previously exposed to these compounds. In dual-choice cotton leaf disk and pepper fruit disk arena assays, caterpillars reared on a normal artificial diet were strongly deterred by strychnine and strophanthin-K. However, caterpillars reared on an artificial diet containing strychnine were insensitive to strychnine and strophanthin-K. Similarly, caterpillars reared on an artificial diet containing strophanthin-K were also desensitized to both deterrent chemicals. Electrophysiological tests revealed that the deterrent-sensitive neurons in taste sensilla on the maxillae of caterpillars reared on each deterrent-containing diet displayed reduced sensitivity to the two chemicals compared with the caterpillars reared on normal diets. We conclude that the experience-dependent behavioral plasticity was partly based on the reduced sensitivity of taste receptor neurons and that the desensitization of taste receptor neurons contributed to the cross-habituation to the two chemicals.
Zhou
Dongsheng
D
Institute of Zoology, The Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, People's Republic of China.
van Loon
Joop J A
JJ
Wang
Chen-Zhu
CZ
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D055724:Electrophysiological Phenomena / Q000187:drug effects / Q000502:physiology; D007814:Larva / Q000187:drug effects / Q000502:physiology; D007915:Lepidoptera / Q000187:drug effects* / Q000502:physiology*; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology; D010675:Pheromones / Q000494:pharmacology*; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000502:physiology; D013328:Strophanthins / Q000494:pharmacology*; D013331:Strychnine / Q000494:pharmacology*; D013649:Taste / Q000187:drug effects / Q000502:physiology
D010675:Pheromones; D013328:Strophanthins; D013331:Strychnine; C029082:strophanthin K