ARS | Publication request: DATA GAPS: LARVAL MOVEMENT, FEEDING PREFERENCES, AND NATIVE HOST-PLANT RESISTANCE

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 28, 1999
Publication Date: N/A

Technical Abstract: The western corn rootworm is a major insect pest in continuous corn production, but no viable alternatives to insecticides are available for its control. Seed companies have announced commercialization goals for transgenic seed with resistance to corn rootworm larval feeding as early as 2001. As part of a symposium on understanding where current information is sinadequate for developing a resistance management plan for slowing the development of resistance to transgenic and/or native resistance genes in corn, our current understanding of host location and larval movement will be presented. Information presented will include a 1998 study conducted in our research group in which plant-to-plant and row-to-row larval movement were evaluated. A center plant was infested with 1,500 viable western corn rootworm eggs and soil cores were taken from the infested plant, the closest six plants within the row, and the four closest plants in the closest two rows. All core samples were placed in Berlese funnels for a minimum of 72 hours. Two row spacings (36 inch and 18 inch) and two plant spacings (6.5 inch and 9.7 inch) were set up using a randomized complete block design with four replications and three sampling dates. Significant movement occurred within the row, but movement across rows was negligible, even for 18 inch rows. These data suggest that a seed mixture of transgenic rootworm resistant seed and nontransgenic seed within a row would not be recommended.