Sunday, November 4, 2007 - 3:15 PM
11-3
Winter Annual Grass Control in Conventional and Glyphosate-Tolerant Winter Canola.
Winter wheat producers in the southern Great Plains are experiencing increasing problems with Italian ryegrass, jointed goatgrass, and feral rye. Growing winter canola in rotation with winter wheat increases herbicide options for controlling these winter annual grass species. However, in winter canola, volunteer wheat can become a weed. Registered herbicides were evaluated for control of these species in conventional and glyphosate tolerant winter canola at multiple locations. The experimental design at each site was a randomized complete block. Plot size was 1.2 by 7.6 m with four replicates. Herbicide treatments were applied using a CO2- pressurized backpack sprayer with 187 L/ha of water carrier for the preplant incorporated treatment and 93.5 L/ha of water carrier plus recommended adjuvants for postemergence treatments. Trifluralin at 1120 g ai/ha was incorporated immediately before planting. Other treatments were applied postemergence in the fall or sequentially in the fall and late winter. Weed control was estimated visually in the spring. Plots were harvested with a small-plot combine. Sub-samples were extracted from each harvested canola sample and weed seed was separated by species and weighted. Canola yields were corrected for weed seed content. All herbicides reduced weed seed content in harvested canola, but differences were found in efficacy of the different herbicide treatments on the various species.
Audio File