Evaluation of alternative tillage systems in the absence of herbicides for maize production in a savannah loamy sand

Abstract

In most parts of eastern Nigeria, conventional tillage for maize production involves the use of a disc plough followed in a separate operation by a disc harrow. Recently, different tillage methods aimed at soil and water conservation have been advocated, including the no-tillage system which relies on herbicides and mulch. Five tillage methods were evaluated for maize production in a loamy sand for 5 years, without herbicides. These systems, of no-tillage, conventional tillage, discing alone, chiselling alone and rotavating alone were evaluated for their effects on soil properties, weed growth, maize yield and net income. No-tillage exhibited significantly higher bulk density, higher cone index and lower porosity at 15 cm depth than the other methods. More weed growth and lower yield were observed with no-tillage compared with the other systems, between which there was no significant difference. Discing alone was found to be the optimum tillage system based on maximizing net income and minimizing soil disturbance and the use of chemicals.