Current weed management tools, challenges, and opportunities for the new winter oilseed crops camelina, carinata, and pennycress

Authors: Bernards, Mark; LEON, RAMON - North Carolina State University

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/25/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: One of the sustainability goals of the airline industry is a 50% reduction in greenhouse gas emissions by 2050 (relative to 2005). This will require a massive increase in the production of new oilseed crops dedicated for aviation biofuels. Adding a winter annual oilseed crop to rotations where fields are historically winter fallow will help meet this demand, and will provide environmental (reduced erosion and nutrient loss) and agronomic benefits (increased soil health) common to winter cover crops. Three potential winter oilseed crops being developed through multi-institution collaborations are camelina (Camelina sativa), carinata (Brassica carinata) and pennycress (Thlaspi arvense). Camelina, also known as gold-of-pleasure or false flax, appears best adapted to the extreme cold of the upper Midwest. Carinata, also known as Ethiopian mustard, is currently adapted to survive the winters of the Southeastern U.S. Both camelina and carinata have been grown as crops for thousands of years in Europe and Ethiopia, respectively. Production of each in North America has been limited, primarily as short-season summer annual crops to diversify small-grain rotations in the Great Plains. Field pennycress, a common weed in temperate climates, is undergoing domestication using mutagenesis and gene-editing. Varieties with improved oil profiles (low erucic acid) and that are non-dormant and non-shattering are being grown commercially on a limited basis in central Illinois. Pennycress has also been grown successfully in research trials in the eastern and northern Corn Belt. Each of these crops has the potential to be grown on millions of hectares in the U.S., but widespread adoption will require effective and affordable weed management options. First, there is limited data on herbicide carryover risk from potential rotation crops (corn, soybean, wheat, cotton, peanut). Research is needed to identify herbicides that do not pose a risk when a winter oilseed is planted within 90-120 days of application, and support from registrants will be needed to update labels of suitable products. Second, successful weed management in an oilseed crops will depend on effective stand establishment and rapid canopy closure. General establishment and growth guidelines have been published by groups promoting adoption of these crops, but there is need to refine agronomic recommendations based on studies conducted across a broader range of environments. Third, a few herbicides are labeled for camelina and carinata because they are part of EPA’s Canola/Rapeseed crop subgroup (20A), but only quizalafop is labeled for pennycress. Work to identify other suitable herbicides and herbicide use strategies, with support from herbicide registrants willing to add these crops to product labels, will be helpful to promote farmer adoption. Fourth, there is a need for data describing the effect growing these winter oilseeds may have on weed management in the following rotation crop. If they are beneficial in suppressing troublesome summer annual weeds through residue or compounds released into the soil, they may provide economic benefits in addition to the sale of the oilseed to incentivize grower adoption.