Nitrogênio e fósforo no crescimento inicial de cedro australiano (Toona ciliata var. australis)

Abstract

The objective of this study was to test diferent doses of nitrogen and phosphorus in the initial growth of Australian cedar to verify what the best treatment for the initial development of the species. The study was conducted in a greenhouse and the soil was used to composse the substrate was the yellow dystrophic latosol. The treatments were constituted of 4 doses of nitrogen (0, 50, 100 and 150 mg/dm3) and 5 doses of phosphorus (0, 150, 300, 450 and 600 mg/dm3). The design was completely randomized with 3 repetitions, totalizing 60 experimental inits. Each experimental unit was composed by cultivaing a cutting in pots with capacity of 1,7 dm3. Significant results were verified to doses of nitrogen and phosphorus for all the variable avaluated. The doses that provided maximum growth of the species for the majority of the variables evaluated were 50 mg/dm3 of nitrogen and 150 mg/dm3 of phosphorus.