Yield and production bienniality of dense coffee plantations under different levels of N and K

Abstract

The objective of this work was to evaluate the effect of N and K fertilization on the yield and production bienniality of dense coffee plantations, in a long‑term study. Two experiments were evaluated in the Zona da Mata region of Minas Gerais, Brazil, under a randomized complete block design, split‑plotted in time. In the first experiment, carried out with 1.5x0.7 m spacing (9,523 plants per hectare), the effects of seven doses of N + K₂O in the proportion of 1:1 were evaluated (0, 200, 400, 600, 800, 1,000, and 1,200 kg ha^‑1 per year) during eight crop seasons (2001/2002 to 2008/2009). Since the fertilizer had 1:1 proportion, in order to obtain the dose for each nutrient (N or K₂O), the total dose must be divided by two. The second experiment was done with 2.5x0.6 spacing (6,666 plants per hectare), under a factorial arrangement, with five doses of N (0, 150, 300, 450, and 600 kg ha^‑1 per year) and five doses of K2O (0, 150, 300, 450, and 600 kg ha^‑1 per year), during six crop seasons (2005/2006 to 2010/2011). The doses related to the maximum yield of processed coffee ranged from 424 to 560 kg ha^‑1, for N, and from 21 to 338 kg ha^‑1, for K₂O. Nitrogen fertilization reduces the effect of production bienniality of coffee plants, and K₂O fertilization, in years of low productivity, promotes yield recovery of coffee plants in the next year.