SOIL LIMING AND NPK FERTILIZATION ON NUTRIENT EXPORT AND QUALITY OF PITAYA

Abstract

Nutrient export provides important information for fertilization decisions in pitaya production. Fertilization management can be planned considering the productivity reached by the orchard, aiming to maintain the fruit quality required by the consumer market. This study evaluated the nutrient export and quality of fruits Selenicereus monacanthus as a function of liming in the soil and NPK fertilization. The treatments were doses of NPK, arranged in a fractional factorial scheme 1/2(4×4×4), distributed in a randomized block design, with four blocks and two cultivation areas, with and without soil liming. The factors were doses of N: 13, 124, 235, and 347 kg ha^-1; P₂O₅: 9, 64, 120, and 231 kg ha^-1; and K₂O: 26, 138, 249, and 360 kg ha^-1. The quantity of nutrients exported per ton of S. monacanthus fruits were: K, 12.65 kg; N, 3.24 kg; Ca, 1.53 kg; P, 0.54 kg; Mg, 0.33 kg; Mn, 166.0 g; Fe, 12.67 g; and Zn, 3.49 g, with liming in the soil. The order of nutrients exported differs in the peel and pulp, being K>N>Ca>Mn>P>Mg>Fe>Zn in the peel and K>N>Ca>P>Mg>Mn>Fe>Zn in the pulp. Liming increases the quantity of nutrients exported to fruits, mainly Ca, P and Mg in the peel. K₂O fertilization in pitaya orchards improves fruit quality. Liming and NPK fertilization should be carried out in pitaya cultivation to adjust nutrient contents in the soil in order to replace the nutrients exported by fruit harvests.