Asian Soil Research Journal

Soil fertility loss due to acidity, depletion of organic matter, climate change, intensive cropping, and excessive use of mineral fertilisers has become a major constraint to crop production and food security in Unwana. To address declining soil quality and low crop production, a study was conducted in the Department of Horticulture and Landscape Technology, Akanu Ibiam Federal Polytechnic, to investigate the effects of poultry manure and black soldier fly frass on soil chemical properties and the growth and yield of pepper. The treatments comprised four application rates (0, 2.5, 5.0, and 7.5 t ha⁻¹) of poultry manure and black soldier fly frass, arranged in a completely randomised design (CRD) under greenhouse conditions using 15-litre-capacity buckets containing 10 kg of topsoil from the Departmental Research Farm. Habanero pepper seedlings were transplanted two weeks after treatment application. Growth data, including number of leaves, plant height, and stem girth, were collected six weeks after transplanting, while yield data (number and weight of fruits) were collected ten weeks after transplanting. Results showed that, relative to the control, poultry manure and frass, applied alone and in combination, significantly improved the soil chemical properties. Among the sole treatments, frass had a greater effect on pH and organic matter, whereas poultry manure consistently improved the other soil chemical properties more than frass. However, the combined application of both amendments had a greater effect than their individual applications, and the combination of 7.5 t ha⁻¹ each of poultry manure and frass generally produced the greatest improvement in soil chemical conditions. Likewise, pepper productivity improved with these amendments compared with the control, and 7.5 t ha⁻¹ each of poultry manure and frass produced the highest recorded yield and is therefore recommended for pepper production in Unwana.