Weathering Rate of Rubber Septa-Impregnated Male Sex Pheromone of Sweetpotato Weevil, Cylas formicarius elegantulus (Coleoptera: Brentidae), in East Hawaii

摘要

In recent years, sweetpotato, Ipomoea batatas (L.) Lamarck, production in Hawaii has been increasing, reaching 243 harvested ha, with a total production of 3.76 million kg in 2009. Sweetpotato production in Hawaii is hindered by three major quarantinepests, for which only one, the sweetpotato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Brentidae), has an identified sex pheromone, (Z)-3-dodecen-l-ol (E)-2-butenoate, that has been deployed in traps for monitoring and suppression of field populations. The longevity of a commercial source of this sex attractant was tested under field conditions on the Hamakua Coast on the island of Hawaii. Based on a linear regression developed from weevil catch results versus weeks of aging, catch dropped to 50% of the catch of unweathered lure at 13.2 weeks, at a lower elevation site, and at 9.0 weeks, at a higher elevation, windier site. Based on these results, lures in traps should be replaced every 9 weeks to maintain at least 50% of maximum trapcatch. Further research is needed to integrate pheromone-baited traps for sweetpotato weevil into a pest management system for sweetpotato pests in Hawaii. Suppression of sweetpotato weevil populations may be enhanced by increasing pheromone concentration in traps.