SPATIAL VARIABILITY OF CORN YIELD DUE TO MACRONUTRIENTS AND PLANT POPULATION

It is important to consider agricultural production with emphasis on sustainability and it is fundamental to consider spatial and temporal variability of yield factors and conduct crop managements under this variability. The objective of the present study was to define management zones in an experimental field cultivated with corn considering the spatial variability of macronutrients and saturation of bases on the soil and their interactions with grain yield and population of normal plants. Soil data was derived from grid sampling, plant population was collected on the same grid, yield was obtained from yield monitor on the whole area and geostatistics tools were used for analysis. Results allowed estimating the levels of phosphorus, potassium, calcium, magnesium and saturation of bases in the soil and establishing management zones for soil fertility based on the population of normal plants and grain yield, considering that the population of normal plants resulted in more effect on grain yield than the soil elementsanalyzed