Growth and Yield Performance of Sweet Potato Using Organic Fertilizer on an Ultisol

Abstract

Continuous cultivation of sweetpotato (Ipomea batatas) on nutrient-depleted soils is a major cause of low yield in tropical Africa. This study evaluated the effect of two organic fertilizers Monty liquid and pig manure on the growth and yield performance of sweetpotato grown on an Ultisol in Akwa Ibom State, Nigeria. A randomized complete block design (RCBD) was used with three treatments: Monty liquid organic fertilizer, pig manure, and a control (no fertilizer). Data were collected on number of leaves, number of branches, vine length, leaf area index (LAI), biomass yield, and root yield. Although statistical analysis revealed no significant differences (p > 0.05) among treatments, numerical variations indicated that pig manure tended to improve vegetative growth and tuber yield compared to Monty liquid and the control. Pig manure produced the highest biomass yield (12.88 t/ha) and root yield (8.41 t/ha), followed by Monty (7.24 t/ha biomass; 6.66 t/ha root yield) and the control (7.00 t/ha biomass; 5.47 t/ha root yield). These findings suggest that organic fertilizer application, particularly pig manure, can improve sweetpotato productivity on nutrient-poor Ultisols.