Population ecology, life history, and biological control of the pepper weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae)

The pepper weevil, Anthonomus eugenii Cano, is the major arthropod pest of peppers, especially Capsicum annuum L., in the Americas. Adult weevils can feed and oviposit on buds, flowers, and fruit. Larvae develop and feed inside those plant structures thus reducing crop yields. To enlarge a management program, methods were developed for rearing the weevil and the developmental biology and life history parameters were determined in the laboratory; survival and reproduction of the weevil were evaluated in field cages during the summer and fall of 1999 and 2000 and the preliminary biology of Triaspis eugenii Wharton and López-Martínez was studied.; Methods were developed for successfully rearing the pepper weevil on jalapeño peppers. The highest production of progeny was obtained at the ratio of five weevils to one pepper fruit, compared to the ratios of 10:1, 15:1, and 20:1. Using seven constant temperatures ranging from 15 to 33°C, A. eugenii developed as a poikilothermic organism with three instars observed at all temperatures. A lower developmental threshold of 9.6°C and a degree-day requirement of 256.4 were estimated for egg to adult development. The optimal temperature for population increase appeared to be 30°C, because at that temperature a maximum fecundity of 3.1 eggs per female per day, the shortest development time of 12.9 days, minimal mortality, and the highest life history parameters were obtained. Anthonomus eugenii adults were observed during the summer and fall in nightshade and pepper plants in field cages. These weevils fed and reproduced when sentinel peppers were offered to them, thus indicating summer-long survival. Management of these host plants during the summer fallow period would reduce weevil populations infesting fall plantings. Triaspis eugenii accounted for 88.4% of all the parasitoids attacking weevils in Nayarit, México. The development time of egg to adult in the laboratory was 16 to 23 days, with males emerging before females. This is the first report of an egg-larval parasitoid attacking pepper weevil. The information collected in this study on the development, life history, summer ecology, and biological control of A. eugenii will help develop management strategies for the pepper weevil.