Abstract

Maize grown during the off season is a viable alternative for the state of Mato Grosso, Brazil. Therefore, the objective of the present study was to investigate the influence of the duration of irrigation with nitrogen doses on the yield characteristics of maize. The experiment was conducted in a greenhouse using a randomized completely block design with a factorial 5×5 matrix corresponding to 5 irrigation durations, the soil water tension at 15, 25, 35, 45 and 55 kPa and five doses of nitrogen (0, 50, 100, 150 and 200 mg dm^-3), with four replications. The experimental units were represented by plastic pots with a capacity of 18 dm³ of soil. We evaluated the productive characteristics of the maize plant. The data were submitted to the F test and polynomial regression. The increased dry mass of the shoot, the root dry mass and the ear length were obtained from the plant under irrigation when the soil reached a 15 kPa tension at doses of 100 and 150 mg dm^-3 of nitrogen. For the weight of 100 grains, no interaction between the factors was found, providing a greater grain yield with 15 kPa and 200 mg dm^-3 of nitrogen alone.

Key words: Zea mays L., tensiometer, nitrogen fertilization.