Abstract
A pot experiment was conducted to determine the effects of potassium on the growth and yield of groundnut on three (3) parent materials. The soils were formed from alluvium, beach ridge sand and coastal plain sand. The physical and chemical properties of the soils were determined. Potassium (K) rates of 0 g (control),15 g, 25 g and 35 g (K2O) were applied to the potted plant. The experiment was a complete randomized design (CRD) arranged in a split plot and replicated three (3) times. The three (3) parent materials occupied the main plot while the K rates occupied the sub-plot. There were a total of thirty-six (36) experimental units. The experiment spanned for four months. The results showed that the soils were light textured, ranging from sand (coastal plain sand), sand (beach ridge sand) to loamy sand in alluvium soils. Soil pH was moderately acidic and values ranged from 5.0 (beach ridge sand) to 5.4 (alluvium). Some soils were low in available N, P, K content, organic matter was low and were significantly different within the parent materials. The coastal plain sand had the highest grain yield of groundnut while alluvium had the lowest. Trends were in these orders: 1,392.67 kgha-1(25g) coastal plain sand > 806.0 kgha-1 (25g) beach ridge sand > 492 kgha-1(35g) alluvium soil. The study showed that 25 g of K produced the highest groundnut grain yield across the parent material.