Variations in Soil Properties and Okra Yield as Influenced by Different Types and Forms of Organic Amendments

The overexploitation of agricultural lands have necessitated the use of fertilizers to enhance food production. However, due to the cost and environmental impacts of mineral fertilizers, the utilization of readily available organic wastes as soil amendments have become necessary. The effect of the sole or combined application of yam, cassava and plantain peels on soil properties was evaluated in an on-farm study conducted at Akufo farm settlement, Ibadan, southwestern Nigeria. The experiment was laid out in a Randomized Complete Block Design with fifteen treatments which consisted of seven amendments (peels of yam (Y), plantain (P), cassava (C), Y+P, Y+C, C+P, Y+C+P) applied in two forms (ground and unground) at a uniform rate of 4 t ha-1 and a control (without amendment). After 3 months of application, the soils were analyzed to determine the effect of the applied treatments on soil properties, after which they were sown to okra. All the amended soils had relatively higher organic carbon, nitrogen, phosphorus and exchangeable bases than the control, but ground treatments performed relatively better than unground ones. Also, irrespective of treatment and form of application, okra yield was considerably improved by the utilized amendments, with ground Y+C recording the highest (14.33 t ha-1). This study showed that the sole or combined use of yam, plantain and cassava peels, either ground as powder or used as mulch, has the potential to improve soil fertility and crop yield and may provide an effective and simple means to utilize organic wastes as soil amendments, especially among poor farmers who cannot afford composting technology.