Submitted to: Entomological Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 8, 2002
Publication Date: November 1, 2002
Citation: FRENCH, B.W., CHANDLER, L.D., HAMMACK, L., BECK, D.A., HARTMAN, D.A. MOVEMENT OF NORTHERN CORN ROOTWORMS IN RELATION TO SEX, SIZE, AND REPRODUCTIVE STATUS IN THE SOUTH DAKOTA AREAWIDE MANAGEMENT SITE. ENTOMOLOGICAL SOCIETY OF AMERICA ANNUAL MEETING. 2002. Paper No. D0335. Technical Abstract: Corn rootworms are economically important pests of maize. Farmers may soon be able to plant Bt maize to reduce CRW populations. One concern is that resistance to the Bt toxin could quickly evolve. Gene flow among resistant and susceptible populations may reduce resistance evolution. Dispersal is a means by which gene flow occurs among populations. Another factor affecting resistance evolution is the mating systems of males and females. We report on the movement of northern corn rootworms (NCR) in relation to sex, size and female reproductive status in the South Dakota areawide management site for 2000 and 2001. We used emergence cages and Pherocon AM yellow sticky traps to capture NCR within maize fields, and sticky traps to capture NCR between fields of continuous maize, first-year maize, and soybean. We placed the sticky traps at different heights between crops. Within the maize fields, sticky traps were placed at silk level and horizontally above the maize canopy to estimate emigration and immigration. Size was estimated based on head width. Female NCR reproductive status was determined as presence/absence of spermatophore (2001 only), presence/absence of sperm in spermatheca, and egg stage - no eggs, with un-chorionated eggs, or with chorionated eggs.