The potential for future commercialization of glyphosate-resistant wheat necessitates evaluation of agronomic merits of this technology. Experiments were established to evaluate glyphosate-resistant wheat and weed responses to glyphosate rate, application timing, and tank mixtures. Glyphosate at 1,680 g/ha did not injure wheat. Wheat response to glyphosate applied to one- to three- or three- to five-leaf wheat was not different from that of untreated wheat. Wheat was injured more from glyphosate plus thifensulfuron or glyphosate plus dicamba than from individual herbicides at one of six locations, but grain yield was not affected by glyphosate tank mixtures. Glyphosate application timing did not affect control of wild oat or common lambsquarters 56 d after treatment. Glyphosate when applied to one- to three-leaf wheat provided better control of wild buckwheat than later glyphosate application, whereas glyphosate applied to three- to five-leaf wheat provided the best control of green and yellow foxtail, redroot pigweed, and Canada thistle. Weed control with glyphosate tended to be better than with conventional herbicides, and wheat treated with glyphosate produced approximately 10% more grain than wheat treated with conventional herbicide tank mixes.

The objective of this study was to compare growth performance and carcass and meat quality characteristics of growing–finishing pigs fed diets containing Roundup Ready wheat (MON 71800), compared with the non-transgenic genetically similar parental control wheat (MON 71900), and four commercial varieties of non-transgenic wheat (HANK, Westbred 926, Express and Zeke). The study was carried out as a split-plot design with a 2 × 6 factorial arrangement of treatments (two genders and six wheat varieties). A three-phase dietary program was used; all diets were formulated with a fixed level of wheat inclusion (70%, 80% and 85% for the Grower, Finisher I and Finisher II phases, respectively). A total of 240 commercial hybrid pigs (equal numbers of barrows and gilts) were grown from 29.5 ± 0.29 to 114.5 ± 2.23 kg live weight in single-gender pens (barrows or gilts) of five pigs (eight pens per dietary treatment) with ad libitum access to feed and water throughout the study. At the end of each dietary phase and of the test period, ultrasound measurements were taken at the 10th rib. Animals from the transgenic (MON 71800) and non-transgenic (MON 71900) treatments were harvested at the end of the study and carcass and meat quality measurements were taken. Pigs fed the six wheat varieties had similar (P > 0.05) feed intake, live weight gain, gain : feed ratio and ultrasound measures of backfat thickness and longissimus muscle area. There was a wheat variety × gender interaction (P < 0.05) for longissimus fat content. Gilts fed the transgenic wheat had higher (P < 0.05) longissimus fat content than those fed the non-transgenic control wheat; however, for barrows there was no effect (P > 0.05) of wheat variety on longissimus fat content. However, there was no effect (P > 0.05) of wheat variety on other longissimus muscle quality or composition measures. Gilts had lower (P < 0.01) feed intake, growth rate and backfat thickness, and similar gain : feed ratio (P > 0.05) compared to barrows. This study, with growing–finishing swine, suggests that the Roundup Ready wheat (MON 71800) resulted in equivalent animal performance to conventional wheat.