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

Double and relay cropping short-season summer annual crops with winter camelina ( Camelina sativa (L . ) Crantz) are strategies to increase bioenergy production without jeopardizing food security. 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 sequentially double cropping a summer annual after the winter crop. Early maturing winter camelina genotypes may improve double cropping productivity in temperate climates. A two-year field study conducted on a Barnes loam soil in west central Minnesota, USA 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 accession (PI650163–1). Also, winter survival, seed yield, and oil content were compared between winter camelina genotypes Joelle, used extensively in previous cropping studies, and PI650163–1. PI650163–1 matured 7–9 d earlier than Joelle with no significant seed yield difference (1184 kg ha −1 ), but lower oil content (370 g kg −1 ). Seed yields of double cropped dry bean and millet were not significantly different than their monocrop counterparts. However, double cropped sunflower was 20 % lower but had similar oil content (499 g kg −1 ) and quality compared with its monocrop check. Seasonal water use of double cropped sunflower was 102 mm greater than its monocrop check and highest across all treatments, which could limit its use in drier environments. Having viable double crop options with sunflower, dry bean, and millet increases rotation options for integrating winter camelina into agricultural systems and might foster farmer adoption of producing camelina for industrial uses. • Winter camelina PI650163–1 matured 7–9 days earlier than Joelle. • Yields and quality of double and mono cropped dry bean and millet were equal. • Double cropped sunflower yielded 20 % less than monocrop check but quality was equal. • Double cropping water use was greater than monocropping but only significant for sunflower. • Double cropped sunflower water use was greatest which may limit its regional use.