Inicial growth of 'Valencia' sweet orange budded on 'Rangpur' lime and 'Swingle' citrumelo was evaluated during the first year after planting, comparing the use of nitrogen soluble fertilizers (urea and ammonium nitrate) and slow-release fertilizer (sulfur coated urea SCU) at 80,0 g N / plant. Fertilizers were applied at four applications as soluble sources and once and twice a year as slow-release source, which was also evaluated at 22,2 and 50,0 g N / plant. Biometric data included: height, trunk diameter, canopy diamenter, leaf chlorofyll concentration and leaf mineral nutrient concentration. 'Swingle' citrumelo induced higher trunk diameter than 'Rangpur' Lime, 12 months after planting. Sources, concentrations and application number of nitrogen did not affect vegetative growth of 'Valencia' sweet orange budded on both rootstocks during the first year after planting.
citrus; nitrogen sources; slow-release fertilizer