Polímero hidrorretentor e fertilização mineral na implantação de híbrido de Eucalyptus urophylla x Eucalyptus grandis

Abstract

The use of water retaining polymer appears as an alternative to provide adequate water the phase of implantation the forest stands, further retaining nutrients necessary for the establishment and development of these. The objective of this study was to evaluate the effect of the water retaining polymer and influence of the different forms of mineral fertilization at growth, content and nutrient accumulation of a clonal hybrid of Eucalyptus urophylla x Eucalyptus grandis in the implantation phase. The experiment was carried out in a randomized complete block design at 2 x 5 factorial scheme, with two polymer doses (0 and 1 g plant-1) and five mineral fertilization combinations (N0P0K0, N0P1K0, N1P0K1, N1P1K1 e N2P2K2, corresponding to the dose of N (N0 = 0, N1 = 62 e N2 = 124 g of fertilizer per plant), P (P0 = 0, P1 = 75 e P2 = 150 g of fertilizer per plant) e K (K0 = 0, K1 = 62 e K2 = 124 g of fertilizer per plant)) in three replications with five plants per plot. The valuates were performed at 30, 60, 120 and 150 days post-planting, when total height and root collar diameter were measured, as well as nutritional chemical analysis, at 150 days. From the obtained data, observed that there was no interaction between the effect of the polymer and doses of mineral fertilization. For the root collar diameter use of the polymer only provided bigger growth seedlings at 30 days the evaluate, and for the height, there was greater growth in the valuates in the 30, 60 and 120 days of planting. The phosphorus treatments were obtained a bigger increment to the diameter in relation for the others 60 days after planting. These the other evaluations of higher fertilizer dosage (N2P2K2) was responsible for the greater growth in diameter and height. The higher dosage of mineral fertilization promoted greater accumulation at NPK in the aerial part of the plants (stem, branches e leaves). Therefore, the polymer gave a higher growth seedling in the initial phase development, and the phosphorus was shown to be essential for the growth in diameter and height in the phase of implantation of the hybrid used