The Influence of Three Years of Tillage and Poultry Manure Application on Soil and Leaf Nutrient Status, Growth and Yield of Cocoyam

Abstract

A three-year (2007 to 2009) study was conducted to evaluate the effect of twenty five tillage-manure treatments on soil and leaf nutrients composition, growth and yield of cocoyam (Xanthosoma sagittifolium). The study was a 5×5 factorial experiment with five tillage methods; manual clearing (MC), manual ridging (MR), manual mounding (MM), ploughing plus harrowing (P+H) and ploughing plus harrowing twice (P+2H) -and five levels of poultry manure (PM) (0, 2.5, 5.0, 7.5, 10.0t/ha). Treatments were replicated thrice. Soil OM, N, P, K, Ca, Mg and leaf nutrients reduced with increase in tillage intensity, thus MC conserved soil nutrients the–most, and increased nutrient uptake. Soil and leaf nutrient concentration was lowest under the P+2H treatment. The MC, MR and MM treatments led to faster growth and higher tuber yield. As poultry manure increased from 0 to 10.0 t/ha soil pH, OM, soil and leaf N, P, K, Ca and Mg increased. The 7.5t/ha PM gave the highest leaf K, Ca and Mg values. Yield and growth parameters of cocoyam increased with increase in PM level up to 7.5t/ha. Out of the 25 tillage cum manure treatments, MC+7.5t/ha PM gave the highest values of yield and growth parameters and was followed by MC+5.0t/ha PM and MC+2.5t/ha respectively.