Efeito da irrigação com água residuária tratada sobre a produção de milho forrageiro

Abstract

The research accomplished with the hybrid forage corn AG 1051, was conducted in the Sewar Treament station of Campina Grande city, Paraíba state, Brazil. The objective was to analyze the residual effects of wastewater and of nitrogen manuring on production of corn with straw, without straw and in grains. The experimental design was in randomized blocks with factorial scheme (2 x 5 + 2), where the factors were: two types of irrigation water (water of municipal supply and treated wastewater), five doses of nitrogen (0, 60, 90, 120 and 180 kg N ha-1 and basal manuring with P and K) and two controls (water of municipal supply and treated wastewater), with four replications. The results showed that there was linear increase in corn production as a function of the increase of nitrogen doses incorporated to the soil, having verified an increment of 21.37% between doses of 0 and 60 kg N, reduction of 12.47% when the dose increased from 60 to 90 kg of N ha-1, increase of the production of 7.07 and 19.9% among the application of the dose from 90 to 120 kg N ha-1 and from 120 to 180 kg N ha-1, respectively; and further the irrigation with wastewater promoted an increment in the production of 144%, compared to the production obtained with municipal supply water.