Growth of corn fertilized with nitrogen and phosphorus in a Yellow Latosol

Abstract

This work was carried out in greenhouse conditions at the Center of Agricultural Sciences of the Federal University of Paraiba, located in Areia, State of Paraíba, Brazil. The main objective was to evaluate the effects of four doses of nitrogen (0, 40, 80 and 120 kg ha^-1 of N) and phosphorus (0, 50, 100 and 150 kg ha^-1 of P₂O₅) on the height of plants (AP), leaf area (AF), stem diameter (DC), shoots dry matter yield (MS) and evapotranspiration (ETc) of a corn crop (Zea mays L. ), cv. Sertaneja. The experiment was carried out in a randomized block design using a 4 x 4 factorial scheme, with three replications. The experimental unit was represented by a plastic recipient with 16 kilos of the first 20 cm a Yellow Latosol. The results showed significant linear effect for  the doses of nitrogen and quadratic for the phosphorus. The dose of 120 kilos ha^-1 of N promoted increases of 41%, 50%, 36%, 26% and 33%, respectively, on the results of AP, AF, DC, MS and ETc, while the maximum results of AP, AF, DC, MS and ETc were verified, respectively, with the applied rates of 137.5, 145.7, 145, 120 and 126.5 kg ha^-1 of P₂O₅. For the soil and climatic conditions of this experiment, application of N and P are necessary to obtain  satisfactory corn yields.