Crescimento de feijão manteiguinha cultivado em solo de cerrado submetido a fontes e doses de nitrogênio

Abstract

The study evaluated the growth of cowpea (Vigna unguiculata) grown in savanna soil under different sources and doses of nitrogen. The experiment was conducted in a greenhouse at the Federal Institute of Amapá (IFAP), Porto Grande Campus, using a randomized block experimental design, with treatments arranged in a 5x2 factorial scheme, corresponding to five nitrogen doses (0, 25, 50, 75, and 100 kg ha⁻¹) and two sources (urea and ammonium sulfate), with four replicates. Biometric parameters such as plant height, stem diameter, dry matter of the aerial part, and weight of 100 seeds were analyzed. The results showed that nitrogen significantly influenced crop development, with urea being more efficient in promoting growth when compared to ammonium sulfate. The dose of 75 kg ha⁻¹ of N represented the point of maximum technical efficiency for most parameters, indicating that nitrogen fertilization should be adjusted according to production objectives. The significant interaction between sources and doses revealed that crop response is dependent on the fertilizer used. The study concludes that the choice of nitrogen source and dose directly impacts the productivity of manteiguinha beans, and it is essential to validate these results in the field for the development of more efficient and economically viable agricultural practices in the Amapá Cerrado.