Productivity and seasonal water use of double cropped dry bean, proso millet, and sunflower after early maturing winter camelina

Authors: Gesch, Russell; Eberle, Carrie; BERTI, MARISOL - North Dakota State University; OTT, MATTHEW - University Of Minnesota; Anderson, James

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/27/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Winter camelina is a new oilseed crop for biofuel feedstock. Because winter camelina can be harvested by early summer, typically enough time remains to grow a second summer annual grain crop (aka: double cropping). Previous research has shown that double cropping with winter camelina works but that improvements are needed to make it more attractive to farmers interested in large-scale production. Also, more data is needed regarding the amount of water needed to grow two crops in a single year or season. In this field study, we experimented with double cropping sunflower, dry edible bean, and proso millet after the harvest of a new early maturing variety of winter camelina (EF-9). We found that the early camelina variety yielded just as well as a variety that we have used in previous research. However, the early camelina was harvested early enough to allow a longer growing season for the second (i.e., double) crops. Results showed that yields and quality of double cropped dry bean and millet were as good as those for the same species grown as single crops at a normal time, but the yield of sunflower was 20% lower. Although seasonal water use was greater for the double crop treatments than the monocrop controls, there was enough soil moisture to produce generally good yields of both crops in the system despite abnormally dry summer conditions during the study period. The sunflower double crop system used the most water, which could be a limiting factor in drier environments than western Minnesota. These results will benefit growers and crop consultants interested in double cropping winter camelina with a summer annual crop and will benefit the specialty seed and biofuel industries as they move forward commercializing camelina.

Technical Abstract: Double and relay cropping short-season summer annual grain crops with winter camelina (Camelina sativa L.) are strategies to increase bioenergy production without jeopardizing food security and may be a way to attract farmers to produce biofuel feedstock. In temperate continental climates, relay cropping, where a summer crop is interseeded into a standing winter crop, maximizes production and economic returns but is more management intensive than double cropping. Also, producing two crops per season, tends to use more water, which could limit the geographical feasibility of dual crop systems. Early maturing winter camelina genotypes are being developed that might be harvested early enough to improve double cropping options in temperate climates, and hence, be more attractive to farmers. A two-year field study was conducted on a Barnes loam soil in west central Minnesota, USA to compared productivity, seed quality, and seasonal water use of double cropping sunflower (Helianthus annuus L.), dry edible bean (Phaseolus vulgaris L.), and proso millet (Panicum miliaceum L.) after an early winter camelina line (EF-9). Also, winter survival, seed yield, and oil content were compared between EF-9 and Joelle winter camelina used extensively in previous cropping studies. EF-9 matured 7 to 9 d earlier than Joelle with no significant yield difference, but lower oil content. Grain yields of double cropped dry bean and millet were as high as their monocrop counterparts, while sunflower was 20% lower but had similar oil content and quality to monocrop sunflower. Generally, double cropping used more water than monocrops. Seasonal water use of double cropped sunflower was 102 mm greater than its monocrop check, which could limit its use in drier environments. Having viable double crop options like that with sunflower, dry beans, and millet might increase farmer adoption of producing camelina for industrial uses.