Efeito da antecipação da adubação sobre o desempenho agronômico da cultura da soja

Abstract

Soybean [Glycine max(L.) Merrill] is the main commodity in the national and global agricultural sector. The average Brazilian productivity is around 3.2 ton ha-1, with the possibility of increasing this value through more complete and technological practices and management. There are several factors capable of influencing the yield of the crop, among them, fertilization stands out, as it is directly related to the entire cultivation system. Fertilization can be carried out in various ways in cultivation environments, among them the inversion or installment of fertilization in the winter crop, which seeks to provide improvements in the availability of soil nutrients, in addition to favoring a greater supply of organic matter, adding numerous benefits to the environment. Thus, it is essential to study agricultural practices that increase productivity. Thus, the objective of this work was to evaluate the agronomic performance of soybeans in relation to different forms of fertilization: total soybean planting; split and with the total inversion in the culture of black oats, combined with four levels of fertilization (0, 100, 200 and 300% of the recommended dose) defined according to the analysis of the soil and production expectation (4.1 to 5 ton ha-1). The experiment was carried out in the municipality of Bom Sucesso do Sul, in the southwestern region of the State of Paraná. They were evaluated in the culture of the black oat green mass and dry mass; and the components of soybean yield: grain yield, weight of a thousand seeds, plant height, number of branches, height of insertion of the first vegetable and number of total vegetables. The data were submitted to analysis of variance and test of comparison of means. The culture of black oats is highly responsive to the increase in fertilizer doses, showing an increase of 30% in the production of dry matter for the doses above the recommended, reaching accumulations of 10.9 ton ha-1 of dry matter. Twice the recommended fertilization (200%) revealed the best yields, both in biomass for black oats and in the grain yield of soybeans. The fertilization of systems, using the management of installment of the fertilization (50% in the black oats and 50% in the soybean) benefits both cultures. This strategy can be adopted without loss of soybean grain yield.