Effect of Tillage Methods on Soil Properties and Sorghum Yield in Kebbi State

This study examines the effect of different primary tillage methods on soil physical properties and grain yield of sorghum in Kebbi State, North West Nigeria. Tillage management significantly affects soil structure, organic matter distribution, water infiltration, and weed pressure, with direct consequences for crop yield. In Kebbi State, conventional deep ploughing is the dominant tillage practice, but its energy cost, soil erosion risk, and potential for long-term soil structural degradation have prompted interest in minimum tillage alternatives. This study establishes a randomised complete block design experiment at Federal University Birnin Kebbi, comparing conventional disc ploughing, ridge cultivation, minimum tillage with zero soil inversion, and zero tillage with herbicide weed control. Soil bulk density, infiltration rate, soil moisture content, weed biomass, and sorghum grain yield are measured over two growing seasons using SAMSORG 14 variety. Findings reveal that ridge cultivation achieves the highest grain yield of 3.4 tonnes per hectare in the first season, attributed to improved water conservation in ridge furrows during dry spells. Minimum tillage produces comparable yields of 3.2 tonnes per hectare with significantly lower fuel and labour costs. Zero tillage yields are constrained by weed competition in the first season but improve in the second season as weed seed bank depletion occurs. The study concludes that ridge cultivation and minimum tillage are superior alternatives to conventional ploughing for sorghum production in Kebbi State conditions. It recommends a phased transition to minimum tillage systems.

Keywords: tillage methods, soil properties, sorghum yield, Kebbi State, minimum tillage.