Comparing The Performance Of Trapping Systems Used In Monitoring And Management Of The Sweet Potato Weevil (Cylas Formicarius) In St. Kitts

The widespread planting of early maturing susceptible varieties of sweet potato coupled with intense mono cropping, has contributed to the build-up of high populations of the West Indian sweet potato weevil pest, Cylas formicarius (Fabricius) (Coleoptera: Apionidae), in St. Kitts over the last two decades. Pest management techniques traditionally rely on cultural practices. In 2000, CARDI introduced a mass trapping technique that involves the use of the funnel trap (FT) fitted with a lure, bought from Great Lakes IPM impregnated with a female sex pheromone that attracts male weevils. By 2007, the Republic of China on Taiwan Agricultural Mission in St. Kitts shared a new trap-lure combination produced by the Taiwan Council of Agriculture (TCOA) with CARDI for evaluation in the field. Studies were done in 2007 to determine the comparative efficacy of the two systems. The traps with their corresponding lures were tested in a typical sweet potato field in Belmont Estate in June, a low rainfall month and again in October during the peak of the rainy season. After two days in the field, weevil catch was counted. This experiment was repeated four times. The TCOA model caught a significantly greater numbers of weevils than the traditional trapping system (P= 0.05). The TCOA caught 1,288(SE 366.26) weevils per day compared to 213 (SE 98.28) weevils per day in the case of the funnel trap. During the wetter part of the year a greater number of insects were captured but there was no significant difference in catch due to seasons. The implications of these findings and the role of mass trapping, as a component of Integrated Pest Management (IPM) are discussed.