Crop species in no-tillage summer crop rotations affect soil quality and yield in an Alfisol

Authors: NOURI, AMIN - University Of Tennessee; LEE, JAEHOON - University Of Tennessee; YIN, XINHUA - University Of Tennessee; SAXTON, ARNOLD - University Of Tennessee; TYLER, DONALD - University Of Tennessee; SYKES, VIRGINIA - University Of Tennessee; Arelli, Prakash

Submitted to: Geoderma
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/13/2019
Publication Date: 3/23/2019
Citation: Nouri, A., Lee, J., Yin, X., Saxton, A.M., Tyler, D.D., Sykes, V.R., Arelli, P. 2019. Crop species in no-tillage summer crop rotations affect soil quality and yield in an Alfisol. Geoderma. 345 :51-62. https://doi.org/10.1016/j.geoderma.2019.02.026.
DOI: https://doi.org/10.1016/j.geoderma.2019.02.026

Interpretive Summary: No-tillage has been recognized as a key conservation management system to preserve soil and water resources and to reduce production costs, while offering multiple benefits to agroecosystems as well as to crop growers. Primarily, due to its potential in soil conservation, no-tillage has become a conventional practice in Tennessee where almost 85% of soybean, 76% of corn and 80% of cotton is seeded. Additionally, winter-cover-crops, as a supplementary source of biomass production on no-till have been used to improve soil quality and help to preserve resources. Due to economic reasons, cover crops are limited to only 4% harvested farmlands in the Southeastern USA. Rotating low-biomass crops in lower frequencies with high-residue grass species such as corn may improve yield and soil quality under no-till practices. This practice can be particularly advantageous in sub-humid climate regions with relatively high organic matter decomposition rates, which may substantially limit soil quality benefits associated with no-till systems. The results suggest that after 15 years of research the presence of corn in cropping systems either as continuous corn or corn in rotation with cotton and soybean is the primary factor contributing to the long-term stabilization of soil structure and increased yield under no-till systems. The results also indicated that corn and cotton yields differed significantly among associated cropping systems while soybean yield did not differ among soybean cropping systems. Corn yield in the corn-soybean rotation was greater than from the cotton-corn rotation and continuous corn, respectively. Cotton in rotation with corn increased cotton yield by 37% compared to the soybean-cotton rotation and resulted in 13% greater yield continuous cotton. Among all three soybean cropping systems, corn-soybean produced highest yield which was followed by soybean-cotton and continuous soybean. Growers in Tennessee may take advantage of these results and adopt the practices for economic gains.

Technical Abstract: Incorporation of cover crops in no-till cropping systems can be constrained by economic and climatic barriers. In such conditions, region-specific crop rotations can diversify and increase the biomass input and improve the soil quality. We evaluated 15-yr impact of six monocropping and double-species rotations of corn (Zea mays L.), soybean (Glycine max L. Merr.), and cotton (Gossypium hirsutum L.) on soil hydro-physical properties and yield on a no-till Loring silt loam at Milan, TN. Incorporation of cotton in the cropping system increased near-surface penetration resistance by 17%. Field soil moisture during dry periods (theta vd) was 18% greater in corn-soybean and continuous corn than other management systems. Including corn in cropping system also improved the wet aggregates stability (WAS) at the surface depth (0-15 cm) and geometric mean diameter (GMD) at 0-30 cm, although these benefits were mainly associated with continuous corn and corn-soybean than cotton-corn. Field-saturated hydraulic conductivity (Kfs) and cumulative infiltration were greater under corn-soybean and continuous soybean while the greatest field capacity (theta FC) and plant-available water content (PAWC) were found in corn-soybean and continuous corn. In accordance with soil properties, corn-soybean produced the greatest corn and soybean yield among all treatments. Cotton-corn, despite showing a non-significant advantage in most soil physical properties over continuous cotton and soybean-cotton (except for greater macroaggregation), produced the greatest cotton yield. Regression analysis indicated the high water retention capacity (theta vd and PAWC) as the common characteristics of high corn and soybean yielding cropping systems.