Diagnóstico da variabilidade da distribuição espacial de plantas de milho no município de Cunha Porã/SC

Abstract

The plant´s arrangement of a crop can be altered through changes in population, in the spacing between rows and in the spatial distribution of plants in the row. The corn is a very sensitive crop to variations in plants arrangement. One of the ways to measure the irregualarity of plants in a crop is through the survey of the Coefficient of Variation (C.V), which provides the variation of the data obtained in relation to the averege, and the lower this value is, the more adequete the distribution of plants in the crop is. Thirty corn crops in the municipality of Cunha Porã-SC were evaluated, each crop data related to plantability were extracted, taking into account the implanted crop with the respective population recommendation of the seed suppliers, the spacing between rows adopted by the producer ad the spacing between the plants in the line, seeking of identify the Coefficient of Variation adopted in the crops in relation of the acceptable limit C.V (20%). All samples of crops, regardless of the cultive showed their C.V above the acceptable minimum, demonstrating that problems related to plantability are present in 100% of the studied crops. Observing the minimum value of losses described in the literature of 64 kg ha-1 for every 10% increase in C.V, the studied crops showed an average of possible losses in the region of 120 kg ha, and when extrapolating this loss by the sum of the area where samples were taken (about 750 ha-1), we arrived at a loss to problems with plantability in the region of 90.000 kg.