Proceedings of the 2019 Mississippi Water Resources Conference

Year: 2019 Authors: Bryant C.J., Krutz L.J., Locke M.A., Steinriede Jr. R.W., Spencer G.D.

Declines of the Mississippi River Valley Alluvial Aquifer are currently unsustainable and require changes to current irrigation practices to ensure irrigated agricultures longevity. However, many environmental and economic factors prevent adoption of systems more efficient than the current furrow-irrigation method. Therefore, methods must be developed to increase the application efficiency of current irrigation systems. This study was established in Stoneville, MS to determine the effects of varying tillage systems with and without cover crops on furrow advance time, runoff volume, and irrigation application efficiency in continuous soybean (Glycine max) production. Treatments consisted of conventional tillage/winter fallow (CT/WF), reduced tillage/winter fallow (RT/WF), reduced tillage with in row sub-soiling (RT/SS), reduced tillage with a cereal rye (Secale cereal) cover crop (RT/RC), reduced tillage with a tillage radish (Raphanus sativus) cover crop (RT/TR), zone tillage/winter fallow (ZT/WF), and zone tillage with a tillage radish cover crop (ZT/TR). Furrow advance time was increased by at least 18% by switching to either zone tillage system or a RT/RC system. Utilizing CT/WF or RT/WF soybean production systems increased runoff volumes by at least 41% while reducing irrigation application efficiency by at least 24%. These data indicate that switching to conservation based soybean production systems that include either zone tillage or a cover crop can reduce runoff water volumes and increase application efficiency of Mid-Southern USA furrow-irrigation systems.