Organomineral líquido: estudo de caso em um cultivo de soja em sequeiro

Abstract

With the country's high dependence on imports of mineral fertilizers, the search for alternatives that reduce this consumption, consider the use of agro-industrial waste as a raw material and promote greater efficiency in fertilizing crops, has motivated the growing interest in the use of organo-mineral fertilizers. In this context, the aim of this study was to compare organo-mineral foliar fertilization with conventional mineral foliar fertilization when growing soybeans in a rainfed system. The variables leaf nutrient content, crop growth and yield were assessed. The experiment was conducted in the municipality of Uberlândia, Minas Gerais, in a randomized block design with seven treatments: five doses of the liquid organomineral fertilizer (1, 2, 3, 4 and 5 L ha-1) plus two additional treatments: the farm standard (mineral foliar fertilization) and the control (no foliar fertilization), with four replications. Two fertilizer applications were made, one at the vegetative stage and the other at the reproductive stage. At 71 DAS, samples were taken for leaf chemical analysis of macro and micronutrients. 40 plants were harvested from the useful area to measure the weight of a thousand grains and yield, and 10 plants from each plot to determine plant height, the number of pods per plant, the number of grains per pod, the number of failed pods and the total number of grains per plant. The data was analyzed for variance using the F test (5% significance) to compare the means and the Dunnet test (5% significance) to compare the means of the additional treatments. The application of liquid organo-mineral fertilizer at different dosages during the vegetative and reproductive stages did not influence growth rates or soybean yields. In nutritional terms, with the exception of nitrogen, the organomineral did not alter the foliar levels of macro and micronutrients. Organomineral and mineral foliar fertilization did not prove to be efficient in improving soybean development and productivity under the soil and climate conditions of this crop.