Improvement of agricultural management through the increased knowledge on production activities has been discussed as decision-making strategies. Real-time field level positioning may allow site-specific investigation of soil and plant variables. In Brazil, the grain crops show great need for research in this area, due to their importance and technological demand. Aimed at discussing some aspects of the increased level of information on an agricultural environment, a field experiment was installed in 1998 in Angatuba, SP, on a grain crop. In an area of 34,3 ha, irrigated by a center-pivot system, monitoring of maize yield was done in the growing season 99/00 besides the soil fertility parameter. Results showed different patterns of yield distribution inside the field, and the causes of observed yield variability. Preliminary analysis of soil data showed low correlation between yield and soil chemical properties in a site-specific base. Observation of yield data suggests the development of strategic management zones, based on trend analysis of the most influent yield components.
precision farming; information technology; GPS; Zea mays L.
