Parcelamento da adubação nitrogenada de cobertura no feijoeiro em sistema de plantio direto

Nitrogen split-application may contribute for the maximization of efficiency of nitrogen use by common bean, to increase grain yield and quality, decrease production cost, and to avoid environmental contamination. The objective of this work was to evaluate the influence of side dressing nitrogen split-application on common bean (Phaseolus vulgaris L.), in a no-tillage system. A randomized complete block design, with four replications, was used. The treatments were constituted by a control (without N application) and five forms of side dressing nitrogen split-application (90-0, 60-30, 45-45, 30-60, and 0-90 kg ha-, applied respectively at V4 and R5 stages). Common bean grain yield and growth in a no-tillage system, are increased by side dressed nitrogen fertilization, independently of the split-application form, at V4 and R5 stages. Split-application, at V4 and R5 stages, has no significant influence on nitrogen use efficiency by common bean, in a no-tillage system. Additional keywords: Phaseolus vulgaris; nitrogen; use efficiency; grain yield.