|Mcgrath, J Mitchell - Mitch|
Submitted to: American Society of Sugarbeet Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2003
Publication Date: 6/30/2003
Citation: Dale, T.M., Renner, K.A., Mcgrath, J.M. 2003. Response of sugar beet (beta vulgaris) varieties and populations to postemergence herbicide treatments. American Society Of Sugarbeet Technologists. p. 779-781.
Technical Abstract: Previous research has shown a differential response of sugarbeet varieties to herbicide treatments. Increased sugarbeet injury may result in reduced yield, sugar content, or both. Preliminary research indicated a differential response of sugarbeet varieties to postemergence herbicides. We conducted an experiment that evaluated the growth response of fourteen sugarbeet varieties, and four USDA sugarbeet populations, to postemergence herbicides applied three times at the micro-rate. Commercial sugarbeet varieties and USDA populations were grown in growth chambers with a photoperiod of 16:8 h (light:dark) and thermoperiod of 14:24 C (day/night). Sugarbeet was treated with the micro-rate of desmedipham plus phenmedipham plus triflusulfuron plus clopyralid plus methylated seed oil at 0.045, 0.045, 0.004, 0.023 kg a.i./ha and 1.5% v/v, respectively, at weekly intervals beginning at the cotyledon growth stage. Sugar beets were arranged in a completely random design with three replicates. Treatments consisted of either treated or untreated sugarbeet. Leaf area and dry weights were recorded one week after the third micro-rate treatment. Sugarbeet varieties varied in their response to micro-rate treatments. Micro-rate treatments resulted in leaf area reduction from 5 to 43%, and dry weight reduction from 22 to 58% among the fourteen sugarbeet varieties. The micro-rate reduced leaf area by 33 to 45% and dry weights by 44 to 54% among the USDA populations. The commercial variety "HM E-17" and USDA population "607XHS" were the most tolerant with a 5 and 33% reduction in leaf area, and 22 and 44% reduction in dry weight, respectively.