Effect of continuous N P K Fertilization on the growth and yield behaviour of coconut with special reference to potash nutrition and its interrelation with other mineral nutrients

Abstract

At the Coconut Research Station , Balaramapuram in Trivandrum District of Kerala State an experiment was laid out in 1964 to assess the growth characters, yield attributes and yield of coconut variety West Coast Tall. The study was further enlarged to include the critical levels of leaf nutrient concentration as related to yield and the soil fertility statusdue to continued NPK fertilization . The treatments consisted of three levels of N, P and K (N-0, 340, and 680 g;P-0, 225 and 450 g and K-0, 450 and 900 g per palm per year). The experiment was laid out in a 3 raise to 3 partially confounded factorial design with two replications. Application of N enhanced the growth characters viz., production of female flowers, percentage fruit set, yield of nuts, weight of nuts, mean thickness and weight of meat, weight of copra and oil percentage. However the effect of N was found to be quadratic at the highest level applied. Application of P although improved the female flower prodcuction, its effect was negative towards copra weight and oil percentage . For the remaining characters studied, the initial level of 225 g per tree per year was found to be adequate.