Development of a Pheromone-Based Trapping System for Rhynchophorus palmarum (Coleoptera: Curculionidae)

Abstract

In tropical America, Rhynchophorus palmarum (L.) is a major pest of coconut, Cocos nucifera (L.), and oil palm, Elaeis guineensis Jacq., through direct attack and as a vector of the red ring nematode, Bursaphelenchus cocophilus Baujard. We have developed an effective trap for this large weevil that employs the newly identified major component of the male-produced aggregation pheromone, 2-methyl-5(E)-hepten-4-ol (rhynchophorol). Trap design, color, placement, and pheromone release rate as well as type, quantity, and longevity of attractiveness of food additives were studied in a commercial oil palm plantation in Costa Rica. Insecticide-treated palm stem pieces baited with rhynchophorol were effective, but buckets or bags with rhynchophorol and insecticide treated sugarcane were the most effective traps. The latter captured 6 to 30 times more weevils than bucket traps containing rhynchophorol or treated sugarcane alone. Trap color did not influence capture rates. More weevils were captured in bucket traps placed at ground level than at 1.7 or 3.1 m. In bucket traps halved sugarcane stalk was significantly more effective than palm pieces, molasses on a sponge, or processed palm mesocarp. Insecticide-treated sugarcane was attractive for 2 wk.