Variabilidade espacial da exportação de nutrientes em soja (Glycine max (L.) Merril)

Abstract

In Brazil, soy is one of the most cultivated crops, due to its different forms of use, and can serve as a source of protein and oil for animals and humans. The demand for soybeans is increasing over the years, making it necessary to search for better yields. Knowledge about the export values of nutrients such as Phosphorus (P) and Potassium (K) is of great importance when thinking about making agriculture more efficient. The objective of the present work was to compare the export data of nutrients P and K available in the literature with export values derived from field samples, considering the existence of spatial variation. The work was conducted at the Capim Branco farm belonging to the Federal University of Uberlândia, in the city of Uberlândia - MG, in the year 2018. Soy was grown in an area of 25ha, the same that was delimited in 50 georeferenced plots, the presence of spatial variability for yield and the nutrient content of the harvested grains. It was possible to observe spatial variation for productivity and for the contents of P and K in the grains. It was also observed that the export data found in the literature can be used to calculate the export of K. For P the results obtained in the laboratory did not present consistency with those found in the literature.