Improving Weed Management in Flax (Linum usitatissimum L.)
Kurtenbach, Moria E 1993-
Flax (Linum usitatissimum L.) is a high utility crop that has value in both food and industrial markets. However, because flax is a poor competitor the presence of weeds can negatively influence its growth and development. The objective of this thesis was to evaluate different approaches to help improve weed management in flax, including new herbicide options and investigating integrated weed management (IWM) methodologies. The goal of the IWM experiment was to identify if different combinations of seeding date (early May vs. late May), seeding rate (400 vs. 800 seeds m-2), cultivar height (short vs. tall), and herbicide rate (0X vs. 1X) could improve the competitive ability of flax. Seeding a tall cultivar, at a high seeding rate, in early May, with an in-crop herbicide resulted in the greatest plant population. Factors that improved crop establishment ultimately had a positive influence on the competitive ability of flax by increasing aboveground crop biomass, crop yield, and reducing aboveground weed biomass. In addition, the goal of the herbicide screening trial was to evaluate the tolerance of flax to Group 14 (PPO inhibitors), Group 15 (VLCFA inhibitors), and Group 27 (HPPD inhibitors) herbicides in comparison to registered industry standards. Seven novel modes of action and three registered industry standards were compared to an untreated check to determine the effect that these treatments had on flax growth and development. Flax showed impressive tolerance to most herbicide treatments, with the exception of those containing flumioxazin. Treatments containing topramezone, pyroxasulfone, and fluthiacet-methyl were found to be generally safe. Overall, initial injury caused by these herbicides was transient and did not translate into any reduction in flax yield or thousand seed weight (TSW) at the majority of sites. Results of this study show that flax has acceptable tolerance of several novel herbicides. Moreover, these herbicides can be combined with several cultural factors to improve the competitive ability of flax and ultimately improve how weeds are managed in this crop.
DegreeMaster of Science (M.Sc.)
CommitteeJohnson, Eric; Pozniak, Curtis; Booker, Helen; Shirtliffe, Steve; Arcand, Melissa
Copyright DateDecember 2017
Integrated Weed Management
Linum usitatissimum L.