NITROGEN DOSES ON THE INITIAL GROWTH AND NUTRITION OF GUANANDI PLANTS

Abstract

The objective of this study was to evaluate the effect of nitrogen doses on the initial development and nutrition of Guanandi (Calophyllum brasiliense Cambèss) plants, a native Brazilian arboreal species. The experiment was carried out in a greenhouse, in plastic containers with capacity of 50 L of dystrophic red Latosol (oxisol). The experimental design used was completely randomized, with six treatments and four repetitions. The treatments consisted of five N doses: 0, 40, 80, 120 and 160 mg dm-3, and the control (with no fertilization or liming of the soil), where urea was used as the fertilization source. With the exception of the control, all the treatments received liming to elevate saturation by bases of soil of 60% and fertilization with 150 mg dm-3 of P2O5, 80 mg dm-3 of K2O. There were monthly analysis of the plant’s height and diameter of the connecting point of root and stem of the plant and at its 10 months age were also analyzed the leaves, stems, roots and total dry mass, the foliar area and the chemical analysis of leaves and stems. The N doses significantly affected the height, foliar area, stem and foliar dry mass data, observing a quadratic effect. The diameter and root dry mass data were affected on a negative linear way. The best growth response was obtained with the 40mg dm-3 N dose.