Submitted to: Florida Entomologist
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/4/2008
Publication Date: 6/1/2008
Citation: Epsky, N.D., Weissling, T.J., Meerow, A.W., Heath, R.R. 2008. Life History and Damage of a new Baradinae Weevil (Coleoptera: Curculionidae) on Amaryllis. Florida Entomologist. 91(2):214-219. Interpretive Summary: A small, black weevil that feeds on amaryllis plants has been known in Florida for at least fifteen years. It is yet to be named taxonomically and its life history has not been studied previously. Therefore, research was conducted by scientists at the SHRS to determine the scope of awareness and concern regarding this pest in the commercial amaryllis industry, and to quantify aspects of weevil life history. Five of thirty growers contacted responded to the survey, and three of those five growers reported damage from this weevil. Additionally, extension personnel in Florida and Georgia have received questions on this pest. Data on developmental time, adult longevity, oviposition, and fecundity were obtained, and pictures of plant damage were presented. This is the first report to quantify the life history of this weevil. This information will provide extension personnel and commercial growers with information needed for management of this pest, and will be used in future research on development of amaryllis varieties that have host plant resistance for this pest.
Technical Abstract: A small Baradinae weevil that feeds on amaryllis plants has been known in Florida for over fifteen years. It is yet to be named taxonomically and its life history has not been studied previously. Observations on weevil damage were made on containerized amaryllis (Hippeastrum hybrids) plants naturally infested in a greenhouse or used for colony rearing. Laboratory studies were conducted at ambient room temperature (75 oC) using excised leaves to obtain information on weevil life history. Adults lived about 3 months, and fed on basal versus apical tissue. Females inserted eggs near the thickened leaf base, and eggs were ~ 0.7 mm long by 0.4 mm. Females laid > 400 eggs over their lifetime, with egg production increasing over the first 7 wk and then tending to decline. Eclosion ranged from ~50% for eggs removed from host tissue within 24 h to ~84% for eggs removed from host tissue within 48 h of oviposition. Eggs hatched after ~7 d and larval development was complete after 29 d of which ~ 10 d were spent as prepupae. Although larvae completed their development on excised leaves in the laboratory, in intact plants early instar larvae tunnel through leaf tissue towards the bulb where they feed and complete development. Under severe infestation, larvae will hollow out the inside of the bulb and may cause plant death. Adult damage is primarily to the foliage through feeding and oviposition. This is the first report to quantify the life history of this weevil.