MODELING THE GROWTH RATES OF AFRICAN YAM BEAN (Sphenostyles stenocarpa) FOLLOWING APPLICATION OF FERTILIZERS

¹Olatunde, A. Olaposi and ²Adarabioyo, M. I

¹Department of Biological Sciences, Achievers University, Owo, Nigeria

²Department of Mathematics, Statistics and Computer & information Systems, Achievers University, Owo,

ABSTRACT

The effect of fertilizer on the performance of three cultivars of African Yam Bean (AYB), Benue Brown (BB) and Emure White (EW) were evaluated in a pot and field trials. The fertilizers were applied as complete NPK (20-10-10) to the soil at the rate of 0 kg/ha, 30 kg/ha, 60 kg/ha, 90 kg/ha and 120kg/ha at planting. Plant vegetative characteristics, dry matter (DM), accumulation and yield characteristics increase progressively as NPK level increased up to 60 kg NPK per hectare before declining in pot and field experiments. The calculated growth rates: Net assimilation rate (NAR); Absolute growth rate (AGR); Crop growth rate (CGR); Relative growth rate (RGR); Specific leaf area (SLA); Leaf weight ratio (LWR); Leaf area duration (LAD) and Leaf area index (LAI) responded positively to NPK fertilization. From this study, it is evident that AYB responded positively to soil applied and 60 kg NPK/ ha seems adequate for optimum growth, flowering, pod formation of the crop under local conditions.