Forage yield and quality of winter canola-pea mixed cropping system

Authors: Begna, Sultan; ANGADI, SANGAMESH - New Mexico State University; MESBAH, ABDEL - New Mexico State University; UMESH, MATHADA - University Of Agricultural Sciences; STAMM, MICHAEL - Kansas State University

Submitted to: Sustainability
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/10/2021
Publication Date: 2/17/2021
Citation: Begna, S.H., Angadi, S., Mesbah, A., Umesh, M., Stamm, M. 2021. Forage yield and quality of winter canola-pea mixed cropping system. Sustainability. 13(4). Article 2122. https://doi.org/10.3390/su13042122.
DOI: https://doi.org/10.3390/su13042122

Interpretive Summary: Dairy farming needs large quantities and a constant supply of quality forage from crops to maximize milk production. The forage crop-dairy farming system in the U.S. Southern Great Plains requires diverse low-input broad leaf crops for sustainability because current practices involve high levels of nitrogen and water for the mono-culture of annual grass-type crops. Winter canola and pea can provide forage crop diversity options with high yields and quality. We investigated winter canola and pea as mono- and mixed-cropping at different seeding ratios for yield and quality in 2015 and 2016 in Clovis, NM. Forage yields averaged over years were equivalent between canola-pea at 75:25 and 50:50 seeding ratios, but higher than mono-pea, mono-canola, and canola-pea cropping at 25:75 seeding ratios. Land equivalent ratio (LER) is a value often used to evaluate crop and land productivity that in all the mixed cropping treatments tested in this study exceeded 1.0, which is the value ascribed to mono-cropping. The highest recorded LER value of 1.15 indicated that mixed cropping systems are better users of land resources. Overall, forage nutritive values were higher in mixed than in mono cropping systems. Canola-pea mixed cropping can be used as an effective agronomic management strategy to enhance forage crop and land productivity, and mechanical harvestability of vining pea. Thus, canola-pea mixed cropping can strengthen the diversity and sustainability of forage crop-dairy farming in the Southern Great Plains under limited irrigation input.

Technical Abstract: Forage crop-dairy farming system in the U.S. Southern Great Plains (SGP) is based primarily on high-input annual grass-type crops in mono-cropping approaches and requires diverse low-input broad leaf crops for strengthening its sustainability. Winter canola (Brassica napus L.) and pea (Pisum sativum L.) have potential to provide forage crop diversity options with high forage yields of high-quality. Winter canola and pea in mono- and mixed-cropping at seeding ratios of canola: pea at 0:100, 25:75, 50:50, 100:0 were studied for yield and quality in 2015 and 2016 in Clovis, NM. Averaged over years, canola-pea at 75:25 and 50:50 seeding ratios produced similar forage yields but higher than mono-pea by 43% and canola-pea at 25:75, and mono-canola cropping by 8%. Land equivalent ratio (LER) of all mixed cropping treatments exceeded 1.0 with canola-pea at 50:50 seeding ratio recorded LER of 1.15, indicating mixed cropping systems are better users of land resources. Total digestible nutrients and relative feed value were higher in canola-pea mixed than in mono-canola and -pea cropping. Canola-pea mixed cropping achieved high yields (13.3 to 14.7 Mg ha-1) of quality forage, improved crop and land productivity with the potential to improve mechanical harvestability of vining pea, and strengthen the diversity and sustainability of forage crop-dairy farming in the SGP under limited irrigation input of ~300mm.