Produtividade e qualidade de frutos de pepino africano em resposta à adubação nitrogenada

Abstract

African horned cucumber (Cucumis metuliferus) is native from Africa and has great potential for international trade of both juice consumption and pharmaceutical uses. However, little is known about the crop management in our conditions, particularly in terms of nitrogen fertilization. This study aimed to evaluate the optimal N level for plant growth and fruit yield as well as fruit quality. The experiment was conducted in a greenhouse using 10 L pots. The experimental arrangement was a completely randomized design with six treatments corresponding to the N rates 0, 40, 80, 120, 160, 200 kg ha-1, with 11 replications. The variables evaluated included fruit yield, shoot dry matter, root dry matter and physical and chemical characterization of the fruits. The number of fruits and weight of fresh matter of fruits per plant presented maximum values of 2.24 fruits/plant and 516.41 g/plant, respectively, for the rates of 122.50 and 154.44 kg ha-1 N. The average weight of fruit was estimated at 240.27 g/fruit at the maximum N level tested (200 kg ha-1 N). The highest shoot dry matter was 39.12 g/plant at 144.00 kg ha-1 N. The N levels did not influence the quality of the fruits. For the cultivation of African cucumber, we recommend the rate of 154.44 kg ha-1 N that provides 2.18 fruits/ plant with average mass of 237.07 g/fruit and yield estimated at 516.41 g/plant.