Tillage Systems and their effects on soil properties, crop growth and shoot yield of Corchorus olitorius (Ewedu)

Abstract

Experiments were conducted in the South West of Nigeria to investigate the effects of tillage methods of Corchorus olitorius (ewedu) for two seasons. on the changes in soil moisture retention, aggregate size distribution and crop performance.
Results showed no-tillage (NT) recorded the highest mean value at saturation (62.5%) and at all the suction points. At 10-20cm soil depth, soil moisture retention was best for ploughing plus harrowing except at 15 bar , where No- tillage gave the highest mean value (5.1%). Mean weight diameter of aggregates (MWD), geometric mean diameter of aggregates (GMD), mean clod size (D50), indices of aggregates size stability were similar among the tillage methods. It was observed that MWD increased for NT and ploughing (PHO) and decreased for ploughing and harrowing (PHA) and ploughing, harrow and bedding (PHB).
The highest values of leaf area and root depth were recorded under PHB treatment (40.75cm2) for the first season while PHO treatment gave the best plant height (42.325cm) for the second season. Shoot yield of “ewedu” was significantly highest (P<0.05) for PHB treatment in both seasons followed by PHO.
KEY WORDS: Yield, moisture retention, tillage systems