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Full-Text Articles in Agriculture

Quantification Of Bt-Endotoxin Exposure Pathways In Carabid Food Webs Across Multiple Transgenic Events, Julie A. Peterson, John J. Obrycki, James D. Harwood Jul 2009

Quantification Of Bt-Endotoxin Exposure Pathways In Carabid Food Webs Across Multiple Transgenic Events, Julie A. Peterson, John J. Obrycki, James D. Harwood

West Central Research and Extension Center, North Platte

Despite the reported specificity of Bacillus thuringiensis proteins against target pests, a number of studies have indicated that the uptake of Bt-endotoxins from bioengineered crops could have negative effects on natural enemies. It is therefore essential to quantify exposure pathways in non-target arthropod food webs across multiple transgenic events. Adult ground beetles (Coleoptera: Carabidae) were collected from transgenic corn fields expressing lepidopteran-specific Cry1Ab, coleopteran-specific Cry3Bb1, and both Cry1Ab and Cry3Bb1 (stacked event), as well as a non-transgenic isoline. Carabid gut-contents were screened for Cry1Ab Bt-endotoxin using enzyme-linked immunosorbent assay. Significant numbers of carabids tested positive for Cry1Ab from the lepidopteran-specific …


Post Weaning Management Of Heifer Calves Impacts Average Daily Gain And Feed Efficiency As Pregnant Heifers, D. M. Larson, Tonya L. Meyer, L. A. Stalker, Richard N. Funston Jan 2009

Post Weaning Management Of Heifer Calves Impacts Average Daily Gain And Feed Efficiency As Pregnant Heifers, D. M. Larson, Tonya L. Meyer, L. A. Stalker, Richard N. Funston

West Central Research and Extension Center, North Platte

Three experiments evaluated replacement heifer development systems and subsequent effects on gain and efficiency of pregnant heifers. In Exp. 1 and 2, were developed grazing corn residue (CR; 422 ± 5 kg) or fed in a dry lot (DL; 446 ± 5 kg) prior to breeding. In Exp. 1, a subset of pregnant heifers (n = 40) were individually fed a diet composed of 90% grass hay (11.7 % CP; DM basis) and 10% of a wet distillers grains plus solubles/straw mixture (21.8 % CP; DM basis) during late gestation. In Exp. 2, 55 pregnant …


The Effect Of Adjuvants, Pesticide Formulation, And Spray Nozzle Tips On Spray Droplet Size, Robert N. Klein, Jeffrey A. Golus, Kelli L. Nelms Jan 2009

The Effect Of Adjuvants, Pesticide Formulation, And Spray Nozzle Tips On Spray Droplet Size, Robert N. Klein, Jeffrey A. Golus, Kelli L. Nelms

West Central Research and Extension Center, North Platte

Many factors, including adjuvants, pesticide formulations, and nozzle tips, affect spray droplet size. It is important to understand these factors as spray droplet size affects both drift and efficacy of pesticides, which is a main concern with pesticide application. A laser particle analyzer was used to determine the spray droplet size and distributions of a range of formulations sprayed through several types of nozzle tips. Nozzles included were extended range flat fan sizes 11003 and 11005 (Spraying Systems XR), air induction flat fan sizes 11005 and 11004 (AI) air induction extended range flat fan size 11005 (AIXR), preorifice flat fan …