Stacked crop rotations and cultural practices for canola and flax yield and quality

Authors: Sainju, Upendra; LENSSEN, ANDREW - Iowa State University; Allen, Brett; Jabro, Jalal - Jay; Stevens, William - Bart

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/4/2020
Publication Date: 2/11/2020
Citation: Sainju, U.M., Lenssen, A.W., Allen, B.L., Jabro, J.D., Stevens, W.B. 2020. Stacked crop rotations and cultural practices for canola and flax yield and quality. Agronomy Journal. 112(3):2020-2032. https://doi.org/10.1002/agj2.20176.
DOI: https://doi.org/10.1002/agj2.20176

Interpretive Summary: Management practices are lacking to enhance yield and quality of important oilseed crops, such as canola and flax, in the semiarid northern Great Plains. Researchers at ARS, Sidney, MT in collaboration with Iowa State University, found that the improved cultural practice increased canola growth and oil concentration compared to the traditional practice in wet years. The improved cultural practice included combination of no-tillage, increased seed rate, banded N fertilization, and increased stubble height and the traditional cultural practice included combination of conventional tillage, recommended seed rate, broadcast N fertilization, and reduced stubble height. Similarly, improved cultural practice and alternate-year crop rotation enhanced flax growth, yield, and oil concentration compared to the traditional practice and stacked rotation in wet years. Producers in the northern Great Plains can enhance canola and flax yield, quality, and oil concentration by adopting the improved cultural practice and alternate-year crop rotation, especially in wet years.

Technical Abstract: Canola (Brassica napus L.) and flax (Linum usitatissimum L.) are important oilseed crops, but management practices to enhance yield and quality are lacking. We studied the effects of stacked versus alternate-year crop rotations and traditional versus improved cultural practices on canola and flax growth, seed yield, oil concentration, and N-use efficiency from 2006 to 2011 in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.) -durum-canola-pea (Pisum sativum L.) (DDCP) and durum-durum-flax -pea (DDFP). Alternate-year rotations were durum-canola-durum-pea (DCDP) and durum-flax-durum-pea (DFDP). The traditional cultural practice included combination of conventional tillage, recommended seed rate, broadcast N fertilization, and reduced stubble height. The improved cultural practice included combination of no-tillage, increased seed rate, banded N fertilization, and increased stubble height. Canola stand count was 36-123% greater with the improved than the traditional cultural practice in 2006, 2009, 2010, and 2011. Canola pod number and oil concentration were 3-36% greater in the improved than the traditional practice in 2007 and 2010, but trends reversed by 5-19% in 2008. Flax stand count was 28% greater with DFDP than DDFP in 2007 and 56% greater in the improved than the traditional practice in 2010. Flax pod number, seed weight, seed yield, N content, N-use efficiency, and N-removal index varied with crop rotations, cultural practices, and years. Canola growth and oil concentration increased with the improved cultural practice as well as flax growth, yield, and quality enhanced with alternate-year crop rotation and the improved cultural practice in wet years.