Field evaluation of repellents against red palm weevil Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) through trap shutdown studies

The red palm weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) is a key pest of palms in diverse agro-systems worldwide. We carried out four field trials in a date palm, Phoenix dactylifera L plantation in Al-Ghowaybah village of Alahsa, Saudi Arabia to screen 45 known insect repellents categorized based on boiling point into four groups (very low, low, medium and high) against R. ferrugineus by ascertaining the extent of reduction in weevil captures in food baited R. ferrugineus pheromone traps (trap shutdown) additionally emitting candidate repellents. Results indicate that the four high boiling repellents tumerone, vanillin, nepetalactone and cinnamic acid can collectively induce a high degree of stimulo-deterrence against R. ferrugineus , with a trap shutdown of 83.8%. These findings offer the possibility of using R. ferrugineus repellents to protect fresh injury sites on palms especially after frond and offshoot removal and also in devising a broader R. ferrugineus semiochemical mediated control strategy by deploying the above repellents as non-host volatiles in the field in conjunction with pheromone (ferrugineol) traps in area-wide push–pull R. ferrugineus control programs.