Effect of Skip-Row Furrow Irrigation on Corn and Soybeans Growth and Yields in Different Soil Types.

Skip-row furrow irrigation (SRI) has been considered as one of the possible ways to improve furrow irrigation efficiency. Limited data is available to determine its effect on crop yield in varying soil textures, root systems, and growing seasons. In this study effect of SRI on corn and soybean growth, grain yield and water savings in a very fine sandy loam and clay soils was evaluated for four years. Irrigation treatments were 1. All Furrow Irrigation (AFI), where every furrow got irrigated 2. fixed SRI, where every odd number furrow received irrigation and 3. Alternate SRI, where irrigation switched between odd and even number furrows. Results of the study showed that SRI could significantly affect the plant nutrient use in light textured soils due to the insufficient water on one side of the row; but clay soil did not affect nutrient use due to the sufficient water getting into the unirrigated furrow through lateral seepage. Similarly, plant growth was also effected in sandy loam soil, while there was no difference in clay soil. In sandy loam soil, compared to AFI, grain yields under SRI were lower by 8 to 47%, depending on the number of irrigations needed, crop growth stage and length of dry spell. In clay soil, SRI had similar grain yields to that of AFI for both corn and soybeans. The maximum yield drop SRI had in clay soil was 12% in the year 2018 that has prolonged dry spell for almost 60 days at critical growth stages. Use of SRI saves about 20 to 30% water in clay soils while no significant yield drop compared to AFI. Use of SRI in sandy loams saves about 40% water; however, it can significantly decrease crop yields, especially under long dry spells, compared to AFI.