ARS | Publication request: Improved growth and nutrient status of an oat cover crop in sod-based versus conventional peanut-cotton rotations

Submitted to: Agronomy for Sustainable Development
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 10, 2009
Publication Date: April 16, 2010
Repository URL: http://hdl.handle.net/10113/42199
Citation: Zhao, D., Wright, D., Marois, D., Mackowiak, C., Brennan, M. 2010. Improved growth and nutrient status of an oat cover crop in sod-based versus conventional peanut-cotton rotations. Agronomy for Sustainable Development. 30:497-504.

Interpretive Summary: Rotation of peanut and cotton with bahiagrass (i.e. sod-based rotation) can greatly improve soil health and increase crop yields and profitability. In the sod-based rotation, the winter cover crop is an important component. The objective of this study was to determine effects of summer crops, cotton and peanut, on growth and physiology of a subsequent oat cover crop in both a conventional (Peanut-Cotton-Cotton) and sod-based (Bahiagrass-Bahiagrass-Peanut-Cotton) rotations. Results from this study indicated that both crop rotation and the summer crop influenced oat cover crop growth, shoot biomass accumulation, plant N, P, and K contents and uptake. Oat grown in plots of the sod-based rotation had greater biomass, leaf chlorophyll and leaf sap NO3-N concentrations as compared to oat grown in the conventional rotation. Oat grown in peanut plots had much greater biomass production and greater tissue N concentrations than oat grown in cotton plots. The increases in cover crop growth and N status found in the sod-based peanut plots was associated with improved soil physical properties, soil fertility, and perhaps other soil quality parameters contributed by the bahiagrass sod. The data gathered from this study can help demonstrate to growers the benefit of growing an oat cover crop and it may help provide N, P and K fertilizer management insight for cotton and peanut nutrient needs in either the sod-based or conventional rotation in the southeastern United States. Our data also may be useful for those producers who manage cover crops for hay or greenchop, by providing them growth response and seasonal nutrient uptake information.

Technical Abstract: Nitrogen (N) leaching from agricultural soils is a major concern in the southeastern USA. A winter cover crop following the summer crop rotation is essential for controlling N leaching and soil run-off, thereby improving sustainable development. Rotation of peanut (Arachis hypogea L.) and cotton (Gossypium hirsutum L.) with bahiagrass (Paspalum notatum) (i.e. sod-based rotation) can greatly improve soil health and increase crop yields and profitability. In the sod-based rotation, the winter cover crop is an important component. The objective of this study was to determine effects of summer crops, cotton and peanut, on growth and physiology of a subsequent oat (Avena sativa L.) cover crop in both a conventional (Peanut-Cotton-Cotton) and sod-based (Bahiagrass-Bahiagrass-Peanut-Cotton) rotations. Two rotations with an oat cover crop were established in 2000. In the 2006-07 and 2007-08 growing seasons, oat plant height, leaf chlorophyll and sap NO3-N concentrations, shoot biomass, and N uptake were determined. Our results showed that the previous summer crop in the two rotations significantly influenced oat growth and physiology. Oat grown in the sod-based rotation had greater biomass, leaf chlorophyll and NO3-N concentrations as compared with oat grown in the conventional rotation. At pre-heading stage, oat in the sod-based rotation had 44% greater biomass and 32% higher N uptake than oat in the conventional rotation; oat following peanut produced 40 to 49% more biomass and accumulated 27 to 66% more N than oat following cotton. Therefore, the sod-based rotation improved not only summer crops, but also the winter cover crop. Increased oat growth and N status from the sod-based rotation indicated greater soil quality and sustainability.