Published online by Cambridge University Press: 27 March 2009
A 2-year field study to investigate the potassium nutrition of groundnut in the lowland tropics showed that a low rate of K is beneficial to the crop. Applied K significantly increased leaf N, seed S, seed P, seed Fe, seed oil and protein content of groundnut. Leaf Ca significantly decreased with increased K application but K treatments significantly increased the seed and shell Ca. Potassium and Ca concentrations were highest in the leaf and lowest in the shell and seed respectively. The significant increases in shell P, shell Ca and shell Fe with increased K application would greatly improve the groundnut shell quality as an animal feed component. The relationship between seed oil and protein content was positive and significant.