Submitted to: Entomological Society of America Annual Meeting North Central Branch
Publication Type: Abstract Only
Publication Acceptance Date: 3/27/2001
Publication Date: N/A
Technical Abstract: If registered, the introduction of transgenic corn will offer a viable alternative to insecticides for managing the western corn rootworm, one of the most economically important pests of corn. Maintaining susceptibility to transgenic crops (resistance management) is in the interest of growers, the Environmental Protection Agency (EPA), and industry, but little is known about many aspects of corn rootworm biology. In 1998, we began a series of experiments to evaluate whether larval movement by the western corn rootworm occurs after initial establishment. In 1998 and 1999, two row spacings and two plant spacings were evaluated with a single infestation level. In 2000, infestation levels of 100, 200, 400, 800, and 1,600 viable eggs on a central plant were evaluated. Movement up to three plants down the row and across a 0.46 m row was clearly documented after initial establishment. In 2000 and a preliminary 1999 experiment, no significant post-establishment larval movement occurred at lower infestations levels. Larvae apparently move when plants are highly damaged and/or when competition for food exists, but the extent that this movement occurs under normal field infestations remains unclear. Another aspect of rootworm biology related to resistance management for which little information is available is the level of importance of alternate hosts in the life cycle of the western corn rootworm. Initial experiments in this area will be discussed.