Effect of different Organic Manures and Mineral NPK Fertilizer on Maize Yield on Volcanic Soils of the Mt Cameroon area under Minimum Tillage

Today, agriculture is characterized by low yields due to continuous cropping and subsequent mining of nutrients without adequate external additions. The study was conducted to examine the effects of different organic manures and mineral fertilizer input on maize grown on volcanic soil of the Mt Cameroon area under minimum tillage. It specifically a) characterize the soils of the area, b) evaluates the physiological growth responses of maize under different external inputs, c) determines their yield responses. An experiment was laid out in randomized complete block design with four replications where maize of the Acid Tolerate Population (ATP) variety was planted. Soil samples were obtained from three different locations on each plot. The samples were analyzed for their physic-chemical properties using standard methods. The maize was evaluated for growth and yield. The data was subjected to descriptive and inferential statistics. The soils of the area were slightly acidic with an average pH value of 6.1. The concentration of calcium and magnesium were low (3.70 cmol(+)/kg) and medium 1.12 cmol(+)/kg), respectively. The average nitrogen content of the soils was very low (0.18%) just as the C/N ratio. Poultry manure fertilization gave the highest yield of 1.4 t ha-1 and the maximum harvest index (17.8%) while the lowest harvest index of 13.60% was recorded in plot where no manure was applied (control). The study, concludes that though organic manures are hailed for their soil amendment properties, the type and duration of handling plays a great role in nutrient availability to plants