Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2006
Publication Date: 4/1/2007
Citation: Duncan, R.E., Ulmer, B.J., Pena, J.E., Lapointe, S.L. 2007. Reproductive biology of Fidiobia dominica (Hymenoptera: Platygastridae), an egg parasitoid of Diaprepes abbreviatus (Coleoptera: Curculionidae). Environmental Entomology 36:376-382. Interpretive Summary: The reproductive biology of a parasitic wasp, Fidiobia dominica, that attacks eggs of the Diaprepes root weevil was investigated in the laboratory. The tiny wasp readily parasitized Diaprepes eggs on both host plant and wax paper substrates. Female wasps were capable of parasitizing more than one egg mass (there were approximately 50 eggs in each egg mass). Female wasps that were provided with host eggs and a honey food source lived significantly longer than those that were not provided a food source; however, they did not parasitize more D. abbreviatus eggs. The wasps were able to lay their eggs in Diaprepes eggs that ranged from zero to seven days old but successful wasp development and emergence declined when the host eggs were four days old or older. Development time, longevity, reproductive period and other demographic parameters of this new biological control agent for the Diaprepes weevil were measured.
Technical Abstract: The reproductive biology of Fidiobia dominica Evans (Hymenoptera: Platygastridae) was investigated in the laboratory using host eggs of Diaprepes abbreviatus (L.) (Coleoptera: Curculionidae). Fidiobia dominica readily parasitized D. abbreviatus eggs on both host plant and wax paper substrates. The number of egg masses parasitized and the number of offspring produced were higher when females were offered more than one host egg mass but did not differ when either 2 or 3 egg masses were offered. Female parasitoids that were provided with host eggs and a honey food source lived significantly longer than those that were not provided a food source; however, they did not parasitize more D. abbreviatus eggs. Oviposition occurred in host eggs from zero to seven days old and host mortality was relatively consistent for eggs zero to five days old, lower for eggs six to seven days old. Successful parasitoid emergence seldom occurred after host eggs were four days old and by seven days no adults successfully emerged. Developmental time from egg to adult was 19.3 ± 0.2 d for males, significantly more rapid than the females (20.4 ± 0.1 d). The mean longevity of adult females was 8.0 (± 0.4) d with a mean oviposition period of 2.7 (± 0.3) d, males survived 8.1 (± 0.4) d. The demographic parameters including intrinsic rate of increase (rm), generation time (T), and net reproduction (Ro) were 0.142 d-1, 22 d and 22.4 female eggs d-1, respectively.