Comparing Soybean Productivity, Soil Health, and Economic Viability Under No-Tillage and Conventional Tillage in the Lower Mississippi Delta

Authors: Anapalli, Saseendran; Mubvumba, Partson; PINNAMANENI, SRINIVASA - Colorado State University; Reddy, Krishna; CORSER, JONATHAN - Mississippi State University

Submitted to: International Journal of Agronomy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/9/2025
Publication Date: 3/4/2025
Citation: Anapalli, S.S., Mubvumba, P., Pinnamaneni, S., Reddy, K.N., Corser, J.K. 2025. Comparing Soybean Productivity, Soil Health, and Economic Viability Under No-Tillage and Conventional Tillage in the Lower Mississippi Delta. International Journal of Agronomy. Volume 2025, Article ID 8878397, 14 pages. https://doi.org/10.1155/ioa/8878397.
DOI: https://doi.org/10.1155/ioa/8878397

Interpretive Summary: In crop production systems, excluding all soil tillage operations (no-tillage) enhances crop residue cover buildup on the soil surface, which protects the soil from rainfall and wind-induced erosion and quality losses. This practice also enhances carbon sequestration and reduces greenhouse gas emissions in crop production systems to help mitigate climate change. When such practices are essential for healthy soils and higher crop yields, their adoption by the farming community is hindered by concerns about their farm production outcomes in location-specific climates and soils. To address this, scientists with the USDA ARS, Crop Production Systems Research Unit, Stoneville, MS, conducted a four-year study (2019 to 2022) in farm-scale plots focused on comparing soybean yield returns and soil health benefits of a no-tillage system against a conventional tillage system in silt loam soil. The plots were maintained under no-tillage corn for over eleven years before the study. In no-tillage, nitrogen and carbon in the soil improved with better water retention. Soybean harvested from no-tillage (5440 kg ha-1) was 1% more than conventional tillage (5480 kg ha-1) management. The study revealed that the adoption of no-tillage in the region potentially increases net returns by reducing tillage-associated expenses without loss in grain yields while conserving the soil and water resources.

Technical Abstract: Conservation agriculture (CA) with minimum to no-tillage (NT) soil management has been widely known for protecting the soil from wind and water erosion and improving soil health and productivity. Uncertainty in farm production outcomes under location-specific NT practices, often with contrasting soils and climates, poses challenges in adopting this practice by the farming community. To address this challenge, a four-year study (2019 to 2022) was conducted on large-scale plots (~ 1.25 ha) focused on comparing soybean [Glycine max (L.) Merr.] yield and soil health benefits of an NT system against a conventional tillage (CT) system in silt loam soil. The NT and CT plots were under corn production over the previous eleven years. Compared to CT, soil bulk density ('b), total nitrogen (TN), and soil organic carbon (C) increased, but field-saturated hydraulic conductivity (Kfs) decreased in the top 10 cm of soil under NT. Higher 'b were also noticed in the 10-30 cm soil depth. There were no significant differences between NT and CT practices in water stable aggregate stability for 0.25 – 0.5, 0.5 – 1.0, 1.0 – 2.0, and 2. 0 – 4 mm aggregate classes. While the higher 'b and lower Kfs under NT can potentially restrict plant root expansion, the beneficial effects of C and TN appear to make up for those adverse effects, culminating in comparable grain yield returns across the tillage systems. Over four years, soybean harvested from NT (5440 kg ha-1) was 1% less than CT (5480 kg ha-1). These results revealed that adopting the NT system can potentially increase net returns by reducing tillage-associated expenses without compromising yields over the four years. of this study in the lower Mississippi delta region with a long-term benefit of natural resource conservation.