Evaluation of pheromone traps for monitoring sweetpotato weevils

Ten types of pheromone traps for monitoring sweetpotato weevils, Cylas formicarius (F.) (Coleoptera: Brentidae), were evaluated in sweetpotato fields at the U.S. Vegetable Laboratory, Charleston, South Carolina, during 2001 and 2002. A funnel trap, a modification of a water-pan trap, and the Pherocon sticky trap were the most effective for capturing male sweetpotato weevil adults. A universal trap, Multipher trap, boll weevil trap, a trap constructed from a five-gallon pail, and a trap made from a milk jug also captured significant numbers of weevils. A Japanese beetle trap and the plastic Pherocon CRW kairomone trap were not effective for trapping sweetpotato weevils. In separate experiments in 2005 and 2006, a trap made from a recycled plastic (PET) soft drink bottle was significantly less effective than the universal trap. Universal traps and PET bottle traps with soapy water were as effective as traps with a dichlorvos insecticide strip for a killing agent. Captures of male sweetpotato weevils in universal traps ranged 0.0-6.0 adults per trap per day during a 6-year period, 2001-2006 at the U.S. Vegetable Laboratory. Except for 2005, when population levels were unusually low, weevil captures increased rapidly during August and continued at high levels until freezing weather in November or December each year. Peak captures were generally from mid-September to mid-October.