Double-cropping effects of Brassica carinata and summer crops: II. Effects of winter cropping history on subsequent summer crop production

Authors: IBOYI, JOSEPH - University Of Florida; MULVANEY, MICHAEL - Mississippi State University; LEON, RAMON - North Carolina State University; DEVKOTA, PRATAP - University Of Florida; BASHYAL, MAHESH - University Of Florida; Balkcom, Kipling; SMALL, IAN - University Of Florida

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/18/2023
Publication Date: 3/27/2023
Citation: Iboyi, J., Mulvaney, M., Leon, R., Devkota, P., Bashyal, M., Balkcom, K.S., Small, I. 2023. Double-cropping effects of Brassica carinata and summer crops: II. Effects of winter cropping history on subsequent summer crop production. Industrial Crops and Products. 197:116609. https://doi.org/10.1016/j.indcrop.2023.116609.
DOI: https://doi.org/10.1016/j.indcrop.2023.116609

Interpretive Summary: There is a potential opportunity for row croppers in the Southeast United States (SE US) to boost revenue by growing winter carinata between summer crops instead of leaving fallow land subject to weeds, nutrient leaching, and runoff. However, a major limitation to the adoption of carinata as a winter crop in the SE US is the lack of information on double-cropping with summer commodity crops common to the region. Researchers at the Univ. of Florida and ARS in Auburn, AL quantified the effects of winter cropping history (carinata vs. fallow) on performance of subsequent summer crops (cotton, peanut, sorghum, and soybean) as part of diversified crop rotations in the SE US. Data was collected on infiltration; plant population; plant height; aboveground biomass; and yield and yield components. Infiltration rates, determined within a week of carinata harvest, were affected by winter cropping history, being greater in former carinata plots than former fallow plots. Carinata harvest coincided with timely planting of cotton and peanut which resulted in these summer crops being sown three to four weeks later than their optimal sowing date for the SE US. Winter cropping history (including winter fallow control) did not influence commodity crop (cotton, peanut, sorghum, and soybean) yields when all summer crops were planted late, as in a double-crop scenario. This study demonstrated that carinata can be successfully grown in the SE US as a replacement for winter fallow, and double-cropped with summer-planted sorghum and soybean with no adverse effect on yield beyond what would be expected from late planting. Double-cropping carinata caused a delay in timely planting of cotton and peanut, and represents a limitation that may hinder the adoption of carinata double-cropping systems in the SE US until a faster-maturing carinata cultivar can be developed. Nevertheless, a winter carinata-summer crop double-crop system may be agronomically viable for the SE US.

Technical Abstract: There is a potential opportunity for row croppers in the Southeast United States (SE US) to boost revenue by growing winter carinata between summer crops instead of leaving fallow land subject to weeds, nutrient leaching, and runoff. However, a major limitation to the adoption of carinata as a winter crop in the SE US is the lack of information on double-cropping with summer commodity crops common to the region. Given that incorporating carinata into the existing cropping systems in the region could influence the productivity of those systems, it is crucial to determine what changes growers should expect. To this end, a study was conducted to quantify the effects of winter cropping history (carinata vs. fallow) on the performance of subsequent summer crops (cotton – Gossypium hirsutum L., peanut – Arachis hypogaea L., sorghum – Sorghum bicolor L. Moench, and soybean – Glycine max L. Merr.) as part of diversified crop rotations in the SE US. A randomized complete block design with eight replications was implemented in Jay, Florida, over three years. Data was collected on infiltration; plant population; plant height; aboveground biomass; and yield and yield components. Infiltration rates, determined within a week of carinata harvest, were affected by winter cropping history, being greater in former carinata plots than former fallow plots. Carinata harvest coincided with the timely planting of cotton and peanut which resulted in these summer crops being sown three to four weeks later than their optimal sowing date for the SE US. Winter cropping history (including the winter fallow control) did not influence commodity crop (cotton, peanut, sorghum, and soybean) yields when all summer crops were planted late, as in a double-crop scenario. In terms of combined productivity of winter (carinata vs. winter fallow) and summer crops, carinata-cotton, carinata-peanut, carinata-sorghum, and carinata-soybean systems were necessarily more productive than their winter fallow counterparts due to no crop production in the fallow during the winter cropping years. Overall, results from this study demonstrate that carinata can be successfully grown in the SE US as a replacement for winter fallow, and double-cropped with summer-planted sorghum and soybean with no adverse effect on yield beyond what would be expected from late planting. Double-cropping carinata caused a delay in timely planting of cotton and peanut, and represents a limitation that may hinder the adoption of carinata double-cropping systems in the SE US until such time a faster-maturing carinata cultivar can be developed. Nevertheless, a winter carinata-summer crop double-crop system may be agronomically viable for the SE US.