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Agronomy Journa l • Volume 111, Issue 2 • 2019 Liquid biofuels are an important component for the transition to renewable energy–based systems (Perlack et al., 2005). Bioethanol derived from sugar fermentation processes from sugarcane (Saccharum L.), sugar beet (Beta vulgaris L.), and corn (Zea mays L.) represents the most common biofuel, which is usually mixed with gasoline (Perlack et al., 2005). When used as oilseed crops to produce biodiesel, soybean [Glycine max (L.) Merr.] and oilseed rape (Brassica napus L.) generate short hydrocarbon chains, so energy-consuming processes are required to generate the longer hydrocarbon chains needed to produce high-energy fuels (Bona et al., 1999; Perlack et al., 2005). Furthermore, there is concern about using traditional food crops for bioenergy production (Erb et al., 2012; Johansson and Azar, 2007). Carinata (Brassica carinata A. Braun), also known as Ethiopian or Abyssinian mustard, is a species with high erucic acid concentration, which facilitates conversion to biofuel (Cardone et al., 2003). It is thought to have originated in northeastern Africa, where it has been cultivated since at least 3000 BC (Alemayehu and Becker, 2002; Simmonds, 1979). This species is the result of chromosome duplication after a hybrid cross between Brassica nigra (L.) W.D.J. Koch and Brassica oleracea L. (Alemayehu and Becker, 2002; Gómez-Campo and Prakash, 1999; Nagaharu, 1935). Although related species, such as canola and oilseed rape (Brassica napus L.), have been commonly grown for oil production in Eurasia and North America (Bona et al., 1999; Perlack et al., 2005), there is current interest in the use of carinata as a winter crop to produce biofuel in subtropical regions. Carinata seems to be more tolerant to warmer environments than canola and oilseed rape (Seepaul et al., 2016). It also has greater shattering tolerance than canola and has a high concentration of very-longchain fatty acids, such as erucic acid, which allows the production of high-energy biofuels, such as jet fuel, with less energy required during refinement (Choudhary et al., 2000; Prakash and Chopra, 1988; Seepaul et al., 2016). Furthermore, because carinata exhibits glucosinolate levels that might negatively affect human health, it is not considered a food crop. However, through breeding and/ or refinement, glucosinolate concentrations can be reduced to levels that allow the use of carinata as seed meal for animal feed after oil extraction (Rosenthal et al., 2017). Brassica carinata Seeding Rate and Row Spacing Effects on Morphology, Yield, and Oil