Nitrogênio e fósforo no desenvolvimento inicial da Campomanesia adamantium (Cambess.) O. Berg cultivada em vasos

Abstract

The aim of this study was to evaluate the effect of nitrogen and phosphorus fertilization in early development of Campomanesia adamantium grown on pots. The experiment was conducted in greenhouse, in the Federal University of Grande Dourados, in Dourados-MS. Five doses of P2O5 were studied (20, 120, 200, 280 and 380 kg ha-1) in the form of simple superphosphate and five of N (6, 36, 60, 84 and 114 kg ha-1) in the form of ammonium sulfate. Treatments were defined using the Plan Puebla III Experimental Matrix, resulting in nine combinations of doses of P2O5 and N, respectively (kg ha-1): 280 and 84; 280 and 36; 120 and 6; 120 and 36; 120 and 84; 200 and 60; 380 and 84, 20 and 36, and 280 and 114. The experimental design was randomized blocks with four replications. The experimental unit consisted of five pots, with one plant per pot. Harvest the whole plant was made to 270 days after transplantation (DAT). It was observed that under higher doses of P and N, at 261 DAT, occurred the highest plant height (38.12 cm), the highest dry weight of leaves (5.68 g plant-1), the largest dry weight of stem (2.13 g plant-1), the highest root dry weight (6.20 g plant-1), the largest stem diameter (6.19 mm) and greatest length of stem and root (20.00 and 13.31 cm). Chlorophyll content was not influenced by the treatments studied, with an average of 36 SPAD (Silicon Photo Diode). Therefore, for conditions similar to those in which the experiment was developing, it is recommended the use of 380 kg ha-1 of P2O5 and 114 kg ha-1 of N for plants production of C. adamantium, up to 270-day cycle.