Phosphate, potassium and magnesium fertilization on oil palm productivity: 12 years of monitoring in the Brazilian Amazon

Abstract

Despite the importance of oil palm, there is little research related to increasing the productivity of the palm under Brazilian conditions, especially in the Amazon region. The objective of the study was to evaluate the effect of phosphorus (P), potassium (K) and magnesium (Mg) on oil palm production during the productive period in the Brazilian Eastern Amazon. The experimental area consisted of 12.64 ha with 1824 trees, spacing was in equilateral triangle (9.00 m between trees and 7.80 m between rows). The adopted design was in randomized blocks, in a factorial scheme 4 × 3 × 2, consisting of four doses of P, three doses of K and two doses of Mg. The evaluation of the experiment began at the 6th year of plant age, and the components of oil palm productivity were evaluated: numbers of fruit bunches per tree (NB), fresh fruit bunches weight per tree (BW), bunch productivity (BP) until the 12th year of plant age. Foliar analysis was performed for the nutrients N, P, K, Ca, Mg and Boron (B). The application of phosphate source promoted increases in NB, BW and BP of oil palm during all the years evaluated. Increasing the K-fertilizer dose implied increases in BW and BP in oil palm trees during all years. The application of Mg-sulfate does not promote an increase in the yield components and foliar Ca and Mg concentration of oil palm, from the 6th to the 12th year of development.