DEVELOPMENT OF A PHEROMONE-BASED TRAPPING SYSTEM FOR RHYNCHOPHORUS-PALMARUM (COLEOPTERA, CURCULIONIDAE)

In tropical America, Rhynchophorus palmarum (L.) is a major pest of co conut, Cocos nucifera (L.), and oil palm, Elaeis guineensis Jacq., thr ough direct attack and as a vector of the red ring nematode, Bursaphel enchus cocophilus Baujard. We have developed an effective trap for thi s large weevil that employs the newly identified major component of th e male-produced aggregation pheromone, 2-methyl-5(E)-hepten-4-ol (rhyn chophorol). Trap design, color, placement, and pheromone release rate as well as type, quantity, and longevity of attractiveness of food add itives were studied in a commercial oil palm plantation in Costa Rica. Insecticide-treated palm stem pieces baited with rhynchophorol were e ffective, but buckets or bags with rhynchophorol and insecticide-treat ed sugarcane were the most effective traps. The latter captured 6 to 3 0 times more weevils than bucket traps containing rhynchophorol or tre ated 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 p alm mesocarp. Insecticide-treated sugarcane was attractive for 2 wk.