Variabilidade espacial da condutividade elétrica aparente do solo e da produtividade do milho de segunda safra

Abstract

The off-season corn crop is grown extemporaneously, from January to June; commonly, its implantation is done soon after the soybean harvest. It has become prominent for its economic return in recent years. Producers have adopted precision agriculture technologies as a strategy in the pursuit of high productivity. In this context, this work aims to evaluate the yield of the off-season corn and its correlation with the apparent electrical conductivity of the soil. The experiment was done at the Belo Horizonte farm in Laguna Carapã-MS. To evaluate the spatial variability of the apparent electrical conductivity of the soil and of the corn yield, a distribution of sampling points was performed using a sampling grid of 72 georeferenced points, where each point represents 0.5 ha, totaling an area of 35 ha. The apparent electrical conductivity, the soil moisture, the plant height, the stem diameter, the mass of one thousand grains, and the crop yield were determined at each point. Descriptive, linear regression and geostatistical analyses were applied to the collected data. According to the maps of yield, soil moisture, plant height, stem diameter, and mass of a thousand grains, it can be attributed that there is a correlation between their values, verified by its spatial variability in the area, and where there was greater apparent electrical conductivity and soil moisture, it is possible to observe a stem diameter, plant height, and also yield greater. It is also possible to conclude that where there were lower values of apparent electrical conductivity in the soil, there was also lower soil moisture, but there are regions of higher soil moisture and higher yield with average electrical conductivity. The soil management strategy used to obtain high yields of off-season corn proved effective, presenting values above those commonly obtained on farms or in regional research.