Extração de nutrientes pela videira 'niagara rosada' enxertada em diferentes porta-enxertos

The objective was to evaluate the influence of rootstocks 'IAC 766', 'IAC 572', 'IAC 313' and 'IAC 571-6' on nutrient extraction by the branches removed by pruning, and bunches harvesting of 'Niagara Rosada', grown in Votuporanga, Sao Paulo state, Brazil. Pruning was done in 08/18/2009, when fresh and dry mass of branches were evaluated, aiming to estimate the biomass accumulation in the branches of the vine. At the harvest, the yield was estimated by the weight of clusters/plant and the number of plants/ha. Samples of branches and clusters were submitted to chemical analyses of nutrients and, based on the accumulation of dry mass of branches and the yield the extraction of nutrients was estimated. We observed for rootstock 'IAC 572' the higher extraction of nutrients by the branches. Referring to the extraction of nutrients by the clusters, we observed a higher extraction for the 'IAC 766'. The differential extraction of nutrients by 'Niagara Rosada' depending on the rootstock, can serve as a basis for the fertilization of the vineyards.