Location: Crop Production Systems Research
2023 Annual Report
Accomplishments
1. Effectiveness of cover crop mixes to promote soil health and minimize yield loss in corn production systems. Winter cover crops can relieve the negative effects that agricultural production has on soil quality and the surrounding environment by decreasing the need for fertilizers and providing natural weed control. However, planting a winter cover crop increases a farmer’s costs and can decrease the summer crop’s yield. Careful selection of cover crop plant species and using mixtures of different cover crops may enhance soil health, improve the release of nutrients back into the soil, and decrease yield inhibition. ARS researchers in Stoneville, Mississippi, conducted a field study on commonly used cover crop species in the region to determine the effects of one, two, and three species mixes on microbial activities in soil, soil nutrient levels, and corn yields. This research showed that two- and three-species cover crop mixes were equally as effective at enhancing microbial activities in soil and increased levels of total nitrogen, phosphorus, and organic carbon in soil by up to 35%. This research also found that cover crop treatments containing only legumes did not inhibit corn yield. These results can be used to make cover crop recommendations to farmers and suggests that a using a grass-legume cover crop mix may provide a balance between soil nutrient enhancement with minimal loss in corn yield.
2. Benefits of crop rotation in cotton and sorghum production compared to no-tillage and winter cover cropping. Row crop production in the Mississippi Delta predominantly involves a mono-culture approach of growing the same crop in the same field repeatedly over several years while tilling the soil and leaving fields bare over the winter months. However, this approach can result in increased erosion, decreased soil health, depletion of soil nutrients, increased need for fertilizers, and ultimately, reduced sustainability for long-term crop production. Incorporating conservation practices such as decreased tillage, summer crop rotation, or planting a cover crop in the winter may improve long-term sustainability in these systems. ARS researchers in Stoneville, Mississippi, conducted a four-year field study to determine the effects of sustainable versus traditional agricultural management practices on soil health and crop yield in cotton and sorghum production systems. This research showed that adding sorghum in rotation with cotton enhances microbial nutrient cycling activities in soils compared to when cotton was grown as a monoculture and that winter cover cropping increased organic matter in field soils by 14%. While cotton yield was not impacted by management, sorghum yield increased 16% when grown with winter cover crops and 28% when grown in rotation with cotton. These results suggest that rotating different plants in a field by either winter cover cropping or summer crop rotation can be an effective tool for farmers to enhance soil health and potentially increase yield in select crops.
Review Publications
Mubvumba, P., Delane, P.B. 2022. Water quality effects of cover crop implementation or tillage in a long-term no-till wheat system. Soil & Tillage Research. 225. Article 105547. https://doi.org/10.1016/j.still.2022.105547.
Kumar, C., Mubvumba, P., Huang, Y., Dhillon, J., Reddy, K.N. 2023. Multi-stage corn yield prediction using high-resolution (UAV) multispectral data and machine learning models. Agronomy Journal. 13(5):1277. https://doi.org/10.3390/agronomy.
Kharel, T.P., Bhandari, A.B., Mubvumba, P., Tyler, H.L., Fletcher, R.S., Reddy, K.N. 2023. Mix species cover crop biomass estimation using planet imagery. Sensors. https://doi.org/10.3390/s23031541.
Pinnamaneni, S.R., Mubvumba, P., Anapalli, S., Reddy, K.N. 2022. Cereal rye cover crop impacts on soybean (Glycine max L.) root growth and soil properties. Frontiers in Soil Science. https://doi.org/10.3389/fsoil.2022.970380.
Parys, K.A., Davis, K.A., James, S., Davis, J.B., Tyler, H.L., Griswold, T.L. 2022. First report of a gynandromorph of Florilegus condignus (Cresson, 1878) (Hymenoptera: Apidae), with notes on phenology and abundance. Journal of Hymenoptera Research. https://doi.org/10.3897/jhr.89.75857.
Hux, B.A., Delaune, P.B., Schirmarcher, M.T., Gentry, T.J., Mubvumba, P. 2023. Winter cover crop impact on soil health and nutrients in texas rolling plains dryland cotton. Agriculture, Ecosystems and Environment. https://doi.org/10.1002/agg2.20352.
Tyler, H.L. 2022. Impact of 2,4-D and glyphosate on soil enzyme activities in a resistant corn cropping system. Agronomy. https://doi.org/10.3390/agronomy12112747.
