Yield Tradeoffs and Nitrogen between Pennycress, Camelina, and Soybean in Relay‐ and Double‐Crop Systems

Abstract

Core Ideas Winter annual oilseed crops are being used in annual cropping systems to add value. We explored trade‐offs in oilseed yield and provision of ecosystem services. Oilseed cover crop yield was greatest when harvested late rather than early. Pennycress and camelina reduced N in the soil profile compared to soybean alone. To gain additional value from land during winter fallow periods in corn (Zea mays L.)–soybean [(Glycine max (L.) Merr.] rotations, growers in the Upper Midwest are considering winter annual oilseed crops such as field pennycress (Thlaspi arvense L.) and winter camelina [Camelina sativa (L.) Crantz]. The objective of this study was to (i) explore trade‐offs between soybean and winter oilseed crop yield as influenced by timing of winter oilseed crop harvest and of soybean planting, and (ii) evaluate how inorganic soil N was affected by the presence or absence of pennycress or camelina. Field experiments were conducted at three sites in Minnesota to evaluate yield of field pennycress and camelina winter oilseed crops planted in a double‐crop system or planted early or late in a relay‐cropping system. Soybean grain yield was reduced in one of the three sites in 2014 and at all sites in 2015. However, the addition of a winter oilseed crop in a relay‐ or double‐crop system increased the total oilseed production. The optimal cropping strategy for achieving maximum total oilseed crop yield was dependent on environment. Winter oilseed crop yield tended to be greatest when harvested late rather than early in either a relay‐ or double‐crop system. Pennycress and camelina significantly reduced inorganic soil N along the entire soil profile compared to soybean alone, especially in the spring (53–72%) and autumn (18–19%) when the potential for N loss is greatest. Pennycress and camelina, when integrated with soybean in a late‐planted relay‐ or double‐crop system, increased total crop yield while providing critical ecosystem services.

Winter Camelina: Crop Growth, Seed Yield, and Quality Response to Cultivar and Seeding Rate

“…Studies that have addressed seeding rates and stand establishment for summer annual camelina frequently demonstrate that yield is little affected over a large range of plant density due to its yield plasticity (Urbaniak et al, 2008;McVay and Khan, 2011;Gesch et al, 2017). The rate for sowing winter camelina tends to be greater than that recommended for spring camelina (Gesch and Cermak, 2011;Johnson et al, 2017), which is assumed partly due to the harsher climate that seeds must germinate and survive in, which can lead to greater stand reduction. The rate for sowing winter camelina tends to be greater than that recommended for spring camelina (Gesch and Cermak, 2011;Johnson et al, 2017), which is assumed partly due to the harsher climate that seeds must germinate and survive in, which can lead to greater stand reduction.…”

“…Interestingly, they found little difference in seed oil content among genotypes within an environment, although across environments, it varied considerably. Moreover, winter annual types autumn-seeded have proven to be freeze-hardy in the northern United States (Gesch and Cermak, 2011;Johnson et al, 2017) and have been demonstrated to be successfully double and relay cropped with soybean [Glycine max (L.) Merr.] Moreover, winter annual types autumn-seeded have proven to be freeze-hardy in the northern United States (Gesch and Cermak, 2011;Johnson et al, 2017) and have been demonstrated to be successfully double and relay cropped with soybean [Glycine max (L.) Merr.]…”

“…and other shortseason summer crops because of their early maturity Berti et al, 2015;Johnson et al, 2017). As a cover crop, winter camelina provides several ecosystem services including soil protection, improved water quality, and forage for pollinators (Eberle et al, 2015;Berti et al, 2017;Johnson et al, 2017), with the added benefit of harvesting its seed for economic return. As a cover crop, winter camelina provides several ecosystem services including soil protection, improved water quality, and forage for pollinators (Eberle et al, 2015;Berti et al, 2017;Johnson et al, 2017), with the added benefit of harvesting its seed for economic return.…”

“…In the only report that could be found for comparing autumn-seeded winter camelina germplasm, Gesch and Cermak (2011) demonstrated that the cultivar 'Joelle' tended to produce greater seed yields and oil content than 'BSX-WG1'. Moreover, winter annual types autumn-seeded have proven to be freeze-hardy in the northern United States (Gesch and Cermak, 2011;Johnson et al, 2017) and have been demonstrated to be successfully double and relay cropped with soybean [Glycine max (L.) Merr.] and other shortseason summer crops because of their early maturity Berti et al, 2015;Johnson et al, 2017).…”

“…Moreover, winter annual types autumn-seeded have proven to be freeze-hardy in the northern United States (Gesch and Cermak, 2011;Johnson et al, 2017) and have been demonstrated to be successfully double and relay cropped with soybean [Glycine max (L.) Merr.] and other shortseason summer crops because of their early maturity Berti et al, 2015;Johnson et al, 2017). Integrating winter camelina as a cover crop into corn (Zea mays L.)-soybean systems has the potential to sustainably intensify crop production on millions of hectares across the US Corn Belt (Sindelar et al, 2017).…”