Oviposition-Deterrent and Repellent Effects of Synthetic Plant-Derived Compounds on the Pulse Beetle, Callosobruchus chinensis (Coleoptera: Chrysomelidae: Bruchinae)

Effects of Synthetic Compounds on Oviposition by Callosobruchus chinensis

Abstract

The pulse beetle, Callosobruchus chinensis (Linnaeus, 1758), is a major stored pest of pulses (Fabaceae) in India. While effective control of this widespread and destructive insect pest is essential, continuous insecticide use poses environmental concerns, thereby necessitating alternative, eco-friendly control methods. This study evaluated the oviposition-deterrent effects of 7 synthetic compounds (linalool, guaiene, citral, estragole, 4-nonanone, alloaromadendrene, and citronellal) on C. chinensis. Linalool showed the strongest suppression of egg-laying at higher concentrations, with the lowest egg count at 500 ppm compared to the control, followed by citral, citronellal, and guaiene. Linalool was also effective in suppressing egg hatching at 500 ppm, followed by guaiene, citral, and citronellal. For percentage reduction of eggs laid and egg-hatching percentage, estragole was highly effective at all concentrations and maintained a high hatching percentage, followed by citronellal. Alloaromadendrene also showed a significant egg-hatching percentage at 100 ppm. Overall, C. chinensis exhibited significant oviposition deterrence in response to linalool, citral, citronellal, and guaiene, supporting the potential of these compounds in sustainable pulse beetle management.