Respuesta del papayo a la fertilizacion con nitrogeno, fosforo y potasio en un Luvisol

Under field conditions, fertilization treatments with N, P, and K were evaluated to determine the response of papaya tree (Carica papaya L.) in terms of growth, yield, and optimum economic dose in a Luvisol in the central coastal region of Veracruz, Mexico. In this study, the factors with their respective levels were nitrogen (N), 0, 150, 300, and 450 kg ha(-1); phosphorus (P2O5), 0, 65, 130, and 195 kg ha(-1); and potassium (K2O), 0, 150, 300, and 450 kg ha(-1). The factors and their respective levels were combined in a design of San Cristobal treatments, which comprised 12 treatments distributed at random in an experimental design of blocks with three replicates. The variables under study were plant height, canopy width, stem circumference, and fruit yield with accumulated commercial value of 23 harvests. The variance analyses for growth variables showed significant treatment effect for plant height, canopy width and stem circumference in 142 days after transplant; for canopy width and stem circumference in 262 days after transplant, and for stem circumference in 382 days after transplant. Such a response was due to the fact that phosphorus applications (P2O5) in general were above the growth variables in comparison to those treatments which did not include phosphorus fertilization. The regression analysis determined a response function with nitrogen and phosphorus effect on fruit yield. It was concluded that 91.787 t ha(-1) was the optimum economic yield obtained with a fertilization of 220 kg ha(-1) N and 145 kg ha(-1) P2O5, generating $112 853.10 ha(-1) as net income and 454% as total capital rate of return.