Export of macronutrients for coffee fruits submitted to different doses of formulation 20-00-20

Abstract

The objective of this study was to quantify the export of macronutrients by coffee fruits Coffea canephora “Conilon - BRS Ouro Preto,” under different doses of the fertilizer formulation 20-00-20 under rainfed conditions, in the Western Amazon. The treatments were six doses of fertilizer 20-00-20, in the proportions: 0; 250; 500; 1,000; 2,000; 3,000 kg ha−1 year−1 and the experimental design was completely randomized with 15 replications. There was a difference for the accumulation of dry mass, content and export of nutrients when comparing straw and grain. The export of nutrients by the grain follows a decreasing order: N > K> Mg > P> Ca > S and the export by straw follows the order: K > N> Ca > Mg > S> P. The doses of the formulation not influence the levels of nutrients in the fruits but promoted an exponential increase in dry mass of grains and straw, with a maximum accumulation of 6,413 kg ha−1 of dry mass of grain and 5,455 kg ha−1 in straw at a dose of 3000 kg ha−1. It is concluded that the doses of fertilizer formulation 20-00-20 do not promote changes in the concentrations of nutrients N, P, K, Ca, Mg, and S in the fruits of the coffee tree “Conilon - BRS Ouro Preto.” However, it promotes greater accumulation of dry mass in both grains and straw and greater export of nutrients by the fruits.