The coconut palm weevil, Rhynchophorus palmarum L. (Coleoptera: Curculionidae) is a serious pest of coconuts (Cocos nucifera L.) in Trinidad. Rhynchophorus palmarum can cause direct as well as indirect damage to coconut trees. Apart from causing death of trees or little leaf syndrome, it is the vector of the nematode Bursaphelenchus cocophilus which causes red ring disease. This disease has been devastating the coconut industry for over 100 years and trees between 3-10 years old are highly susceptible. Management of the disease has been through field sanitation and trapping of R. palmarum. Trapping of the vector has been demonstrated to reduce the incidence of red ring disease in Malaysia, Brazil and Costa Rica. Traps were used with the aggregation pheromone Rhynchophorol (Rhyncholure®) together with sugarcane or fruit baits and an insecticide. In September 2010 a pre-trial was initiated at four locations in Trinidad to examine the efficacy of using baited traps with Rhyncholure® in reducing populations of R. palmarum. Each location was isolated from one another by several kilometres and comprised approximately 1.0 hectare with about 200 coconut trees that were less than 10 years old. At each location one trap made of a discarded 4-litre oil container containing the lure, sugarcane bait and a carbamate insecticide was placed about 1.5 metres high on a leaf petiole close to the trunk of the coconut tree in the middle of the field. The traps were examined weekly for a period of 16 weeks and the number of coconut palm weevils was recorded. The sugarcane bait and insecticide were changed bi-weekly. A total of 651 of these insects was collected over the period with the highest number at Centeno (255) followed by Valencia (186), Carlsen Field (151) and Kelly (59). The results show that the trapping system used was effective in trapping R. palmarum and thus reduce their population in the environment. Based on the data gathered, long term trials will now be established to manage R. palmarum and in so doing manage the spread of Bursaphelenchus cocophilus the causal organism of red ring disease.


Downloads Statistics

Download Full History