Response of okra, Abelmoschus esculentus (L.) Moench, to biochar derived from cocoa pod husk and NPK fertiliser

Abstract

The potentials of biochar derived from cocoa pod husk are currently being explored to improve soil fertility, enhance crop production and prevent the deleterious effect of inorganic fertiliser on the environment. Field investigations were conducted to evaluate the effectiveness of NPK fertiliser fortified with biochar on the growth and yield performance of okra, Abelmoschus esculentus (L.) Moench, relative to inorganic fertiliser. Treatments involved NPK only applied at 30 and 60 kg N/ha, NPK at 30 kg N/ha together with biochar at 2.5 t/ha, NPK at 60 kg N/ha together with biochar at 5 t/ha and a control treatment, without fertiliser or biochar application, laid out in a randomised complete block design with three replications. Growth and yield parameters, plant height, number of leaves, fruit yield, nutrient uptake, post-cropping effects on soil properties were determined. Data were analysed using ANOVA. Growth and yields from the treatment with NPK at 60 kg N/ha, together with 5 t/ha biochar, were significantly (P ≤ 0.05) highest, than other treatments, and partial budget analysis indicated highest marginal rate of returns for this treatment. Soil pH improvement underscored the beneficial effect of NPK fortified with biochar on the nutrition of okra plants, confirming that these materials could be utilised for crop production in the soil of the experimental site.