TEORES DE NUTRIENTES FOLIARES NO MARACUJAZEIRO-AMARELO ASSOCIADOS À ESTAÇÃO FENOLÓGICA, ADUBAÇÃO POTÁSSICA E LÂMINAS DE IRRIGAÇÃO

A field experiment was carried out, in Rio de Janeiro State, Brazil, to evaluate the effect of potassium fertilization and irrigation treatments, on the nutrients N, P, K, Ca, Mg, S, Zn, Fe, Cu, B, Cl, Mn and Na in leaf contents in yellow passion fruit (Passiflora edulis f. flavicarpa). Were tested, on a Rhodic Paleudult soils, four rates of potassium (76, 307, 531 and 764 g plant-1 year-1 of K), utilized potassium chloride, and six irrigation levels (0, 25, 50, 75, 100 and 125% of ETo - reference crop evapotranspiration for grass), in a factorial scheme 4x6. The nutrients leaf contents, at maximum fruit yield (41.3 t ha-1), ranged from 34.7 to 49.8 g kg-1 of organic N, 1.51 to 1.80 g kg-1 of NO3-, 2.31 to 3.43 g kg-1 of P, 23.5 to 35.5 g kg-1 of K, 10.6 to 15.1 g kg-1 of Ca, 2.13 to 3.62 g kg-1 of Mg, 3.19 to 4.33 g kg-1 of S; from 0.96 to 2.31 g kg-1 of Na, 16.9 to 28.9 g kg-1 of Cl, 77 to 135 mg kg-1 of Fe, 50.1 to 91.4 mg kg-1 of Mn, 26.1 to 37.6 mg kg-1 of Zn, 4.53 to 95.4 mg kg-1 of Cu, 22.8 to 54.5 mg kg-1 of B and from 0.96 a 2.31 g kg-1 of Na. Potassium fertilization increased leaf contents of the K and Cl and decreased Mg, Mn, Zn and Na. Irrigation influenced leaf contents of the N, Cl and Na and did not affect the leaf contents of the others nutrients.