Environmental Entomology

Cuda, J.P. and Burke, H.R. (1991) Biology of Trichobaris bridwelli (Coleoptera: Curculionidae), a possible agent for the biological control of Datura stramonium (Solanaceae). Environmental Entomology, 20(3): 899–908.

Abstract

The weevil Trichobaris bridwelli Barber is a natural enemy of jimsonweed (Datura stramonium L.) in the southern United States. The temporal distribution of all life stages showed that T. bridwelli is bivoltine in central Texas and overwinters principally in the adult stage inside the seed capsules of jimsonweed. Females oviposited in the leaves, flowers, and capsules. Subsequent development occurred both in the stems and capsules of its host plant. All life stages of T. bridwelli were attacked by hymenopterous parasitoids; Anaphes sp. and Microctonus sp. are new host records. In the laboratory, adult females lived an average of 16.1 wk and deposited an average of 324 eggs. Development in the laboratory required 37.8 d: egg 5.9 d, larval stage 20.2 d, prepupal period about 3 d, and pupal stage 8.7 d. The intrinsic rate of increase ( Tm ) of T. bridwelli was calculated from laboratory life table data to be 0.41 at 24°C. T. bridwelli was evaluated for its potential effectiveness as a biological control agent of jimsonweed and possibly chinese thornapple, Datura ferox L. Although T. bridwelli did not complete development on a critical test plant (tobacco) under laboratory conditions, extensive host specificity testing should be conducted to determine the limits of its host range.