Influence of Planting and Irrigation Levels as Physical Methods on Maize Root Morphological Traits, Grain Yield and Water Productivity in Semi-Arid Region

Abstract

Assessing the impact of planting methods and irrigation levels is needed to determine the effects on maize root morphological traits, grain yield, and water productivity in semi-arid regions. A study was initiated on maize (Zea mays L.) from 2015 to 2016, including three planting methods [i.e. broad bed and furrow (BBF), shallow and narrow furrow (SNF) and deep and wider furrow (DWF)] and four irrigation levels [i.e. irrigation once in ten days (I10D), irrigation at 40% depletion of available soil moisture (DASM, I40), irrigation at 50% DASM (I50) and irrigation at 60% DASM (I60)] arranged in a split-plot design with three replications. Results reveal that the DWF method has increased root length, root volume, root surface area and root dry weight compared to SNF and BBF (p < 0.05). DWF and SNF resulted in higher grain yield than BBF, although the DWF grain yield was non-significant with SNF but resulted in 22.40% higher irrigation application. Irrigation at I50 had a significant effect on root length, root surface area, and grain yield, regardless of planting methods. Therefore, where irrigation has been a costly and limited farm input, the practice of SNF and deficit irrigation (I50) could be a viable option for greater water saving and higher grain yields of maize.