Submitted to: International Society of Citriculture Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/7/2005
Publication Date: 11/1/2006
Citation: Pena, J.E., Hall, D.G., Nguyen, R., McCoy, C., Lapointe, S.L. 2006. Recovery and establishment of hymenopterous parasitoids released for biological control of the Diaprepes root weevil (Coleoptera: Curculionidae) in Florida. In Proceedings: International Society of Citriculture. Interpretive Summary: This paper presents a review of efforts (1997-2004) to establish natural control in Florida of the Diaprepes root weevil using parasitoids that attack eggs of the weevil. No permanent establishment occurred following releases of one parasitoid (Ceratogramma etiennei Delvare (Hymenoptera: Trichogrammatidae)), but good establishment of two other parasitoids (Quadrastichus haitiensis (Gahan) and Aprostocetus vaquitarum (Wolcott) (Hymenoptera: Eulophidae)) appears to have been achieved at least in southern Florida. Recoveries of these two parasitoids in southwestern, southeastern, and central Florida have been erratic, whereas recovery has been continuous in extreme southern Florida.
Technical Abstract: Three exotic parasitoids, Ceratogramma etiennei Delvare (Hymenoptera: Trichogrammatidae), Quadrastichus haitiensis (Gahan) (Hymenoptera: Eulophidae) and Aprostocetus vaquitarum (Wolcott) (Hymenoptera: Eulophidae) of eggs of the Diaprepes root weevil were introduced from islands in the Caribbean Basin into Florida between 1997 and 2000. Pre-release host specificity tests were conducted in the laboratory for C. etiennei and Q. haitiensis. In addition to eggs of Diaprepes root weevil, C. etiennei and Q. haitiensis parasitized eggs of Pachnaeus sp., but failed to parasitize eggs of other weevil species and coccinellids (Oxyops vitiosa and Cycloneda sanguinea) or representatives from six lepidopteran families (Papilionidae, Danaidae, Nymphalidae, Lycaenidae, Heliconiidae and Pieridae). Releases of the three egg parasitoid species were conducted at multiple locations over a period from 1998 through 2002. Results of yearly surveys conducted during 1998-2002 are summarized and expressed as recovery rates. Recovery rates are the percentage of times that a parasitoid was found based on the number of sampling events over time. C. etiennei was recovered one year after its release, but was not recovered between 2000 and 2002. Q. haitiensis had a recovery rate of 12 to 72% between 2001 and 2002 and A. vaquitarum had a recovery rate of 6 to 100% between 2001 and 2002, depending on location and host plant surveyed. Recoveries of parasitoids in southwestern, southeastern, and central Florida were erratic, whereas recovery was continuous in southern Florida.