Skip to main content
Oviposition and Larval Bionomics of Two Weevils (Coleoptera: Curculionidae) on Sunflower
Faculty Publications: Department of Entomology
  • Gary J. Brewer, University of Nebraska-Lincoln
Date of this Version

Published in Annals of the Entomological Society of America 84(1): 67-71 (1991). Copyright 1991 Entomological Society of America. Used by permission.

Use of cultivated sunflower (Helianthus annum L.) as a host by two species of seed weevils, Smicronyx fulvus LeConte, the red sunflower seed weevil, and S. sordidus LeConte, the gray sunflower seed weevil, was compared using dissection of achenes from naturally and artificially infested plants. The gray seed weevil oviposits on the tips of unopened sunflower florets before anthesis. Larvae migrate through the corolla tube, penetrate the developing achene, and begin extensive feeding at the achene base. Achenes infested by the gray sunflower seed weevil are enlarged, lack an embryo, and appear to be a type of gall. The red sunflower seed weevil oviposits internally in more mature achenes after anthesis has begun, and these achenes have well-developed seed embryos.
Citation Information
Gary J. Brewer. "Oviposition and Larval Bionomics of Two Weevils (Coleoptera: Curculionidae) on Sunflower" (1991)
Available at: