|French, Bryan - Wade|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/31/2006
Publication Date: 11/5/2006
Citation: Ellsbury, M.M., French, B.W., Head, G.P., Noble, C.W., Fuller, B.W. 2006. Spatial considerations in a replicated-plot study of ground beetles (coleoptera: carabidae) in rootworm-resistant maize. Meeting Abstract for International Working Group on Ostrinia and Other Maize Pests (IWGO) Diabrotica subgroup meeting, Vienna, Austria, November 5-8, 2006. Interpretive Summary:
Technical Abstract: Ground beetles (Coleoptera: Carabidae) are of particular interest in agroecosystems because they are effective predators of soil and canopy-dwelling pests and also are considered positive indicators of sustainability. There is concern that ground beetles may be adversely affected by plant-incorporated insecticides in Bt-maize for management of corn rootworms. In a series of field experiments, we tested hypotheses that ground beetles, as indicator species, are unaffected by the genetically-modified corn rootworm-resistant maize. Three experimental treatments, a resistant maize incorporating the Cry3Bb1 gene derived from Bacillus thuringiensis (Berliner) subsp. Kumamotoensis (Bt-based line), an insecticide-treated isoline, and an untreated maize isoline were included in a random complete block design with four replications. Each maize treatment plot was 2 ha and was bounded by soybean alleyways and borders of about 19 m. Crop-specific spatial distributions, influence of topography, and soil apparent electrical conductively on beetle spatial distributions were apparent in georeferenced data taken from a grid array of pitfall traps (N=105) for ground beetles. There were no apparent effects of plant-incorporated insecticides (BT-maize) on ground beetle spatial distributions, thus further supporting the benign nature of these hybrids on non-target ground beetle communities.