VIABILIDADE ECONÔMICA E AGRONÔMICA DE ADUBAÇÃO NITROGENADA E POTÁSSICA EM MILHO

Abstract

Farmers are mostly price takers and can not pass on their costs to their consumers. It is therefore important to have a good management of production costs. The objective of this work was to evaluate the economic feasibility of nitrogen and potassium fertilization in the maize crop in a dystrophic Yellow Latosol. The experiment was conducted at the Chã-de-Jardim experimental farm belonging to the Agricultural Sciences Center (CCA) of the Federal University of Paraíba (UFPB), in the city of Areia-PB, located in the geographic microregion of Brejo Paraibano, with reference coordinates 6 ° 58'11.4 "S 35 ° 43'50.8" W. It was repeated for four years in 2013, 2014, 2015 and 2016, always implemented in the second half of April, with the variety AG 1051. For price estimates, the quotation of the fertilizers with CONAB was raised, corn quotations were made together the main means of disseminating national prices. Costs that were not fertilizer were calculated for a typical household production system in the state. The results were analyzed in the statistical analysis program SAEG, generated equations of responses to productivity and with these equations estimated the productivity for the other doses of fertilizers. The dose of the best agronomic response varies according to rainfall of each year. In years of good rainfall, doses greater than 70 kg of potassium and between 64 and 68 kg of nitrogen should be applied in order to have the best economic result in the production of grains. In years of low rainfall nitrogen doses higher than 90 kg and doses of potassium between 35 and 44 kg should be applied in order to minimize the losses and rely on the strategy of storage of the production so that it can be commercialized when it reaches at least the cost price.