The American palm weevil Rhynchophorus palmarum L. (Coleoptera: Curculionidae) is the most important pest of the coconut palm tree. Its larvae feed on plant tissues and the adult is the main vector of the red ring disease caused by the nematode Bursaphelenchus cocophilus (Cobb) Baujard. The aggregation pheromone 6-methyl-(2E)-hepten-4-ol (Rhynchophorol) has been used as part of the integrated pest management of coconut in several countries, including Brazil, where the pheromone is synthesized and distributed to coconut producers. The use of imported reagents makes the synthesis of the pheromone very expensive. Therefore, this work aimed to verify the efficiency of different release rates of the pheromone in capturing adults of the American palm weevil in the field. When kept inside Eppendorf vials, containing a small hole on the lid (1 mm), the mean release rate of the pheromone was 4.3 mg/day. Weevil catches by pheromone traps baited with pieces of sugar cane and Rhynchophorol at release rates of 4.3 mg/day; 8.6 mg/day; 17.2 mg/day; 34.4 mg/day and 68.8 mg/day, during 60 days, showed that the release rate of 4.3 mg/day was the most economic because all the release ratesdid not capture, but allowed the capture of equal number of weevils. Weevil catches by pheromone traps baited with Eppendorf vials without a hole on the lid, were significantly lower than those traps baited with vials containing a hole. Vials without holes on the lid release 2.2 mg/day of Rhynchophorol in the environment.
Insecta; Rhynchophorol; coconut palm weevil; pest control
