EVALUATION OF NEEM LEAF AND WOOD ASH EXTRACT ON SOIL PROPERTIES, GROWTH AND YIELD OF PEPPER (Capsicum annuum L.)
Keywords:
Bio-fertiliser, Capsicum annuum, Neem leaf extract, Wood ash extract, Pepper yieldAbstract
High cost and environmental impacts of inorganic fertilizers necessitate sustainable, locally available nutrient alternatives, while the interactive effects of organic liquid amendments, application time and rate on soil health and pepper productivity data is limited. This study evaluated the effects of neem leaf and wood ash extracts, application time and rate on soil chemical properties, growth and yield of pepper (Capsicum annuum L.) in Ilorin, Nigeria. A pot experiment was conducted at the University of Ilorin, Nigeria, during the 2025 rainy season using 90 experimental sacks, each containing 10 kg of sandy loam soil, arranged in a split-split-plot design with three replications. Treatments comprised two bio - fertiliser (neem leaf and wood ash extract), three application time (2 weeks before transplanting 2WBT, at transplanting AT and 2 weeks after transplanting 2WAT), and five application rates (0, 25000, 50000, 75000 and 100000 L ha⁻¹). Data were subjected to analysis of variance, and treatment means were separated using LSD test at 5% probability level. The pre-planting soil was sandy loam with low available phosphorus. Both bio-fertilisers maintained favourable soil pH after harvest and slightly increased exchangeable cations and organic carbon. Bio-fertiliser did not significantly affect fruit yield, however, application time and rate significantly (P ≤ 0.05) influenced productivity. Application at 2 WBT produced the highest fruit yield (1.86 t ha⁻¹), whereas 75,000 L ha⁻¹ recorded the highest fruit yield (2.66 t ha⁻¹) and fresh fruit weight (0.0133 kg plant⁻¹). Application of either extract at 75,000 L ha⁻¹, particularly 2 WBT, therefore shows potential for improving pepper productivity while maintaining favourable soil chemical properties and may provide a low - cost nutrient management option for smallholder production.
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