Balanco hídrico num latossolo vermelho escuro álico cultivado com milho com irrigação por aspersão.

The water balance components were determined for cerrado soil planted with corn (Zea mays L.) under sprinkler irrigation conditions. A neutron probe was used to determine the soil moisture profile, which was then used, in association with soil water potential, to estimate deep percolation and evapotranspiration fluxes. The method used to estimate deep percolation and evapotranspiration fluxes proved to be reliable for soil water stress condition and unreliable for rainy day condition, when water storage increased in the soil profile. The upward movement of soil water was the major source of water supply for corn growth, mainly after a shortage of water in the soil profile. Deep percolation represented up to 67% of total water loss (Through drainage and evapotranspiration). The averages for evapotranspiration fluxes, with no water stress condition, were: 1,94mm day -1, for 42 through 60 days after planting; increasing to 5,19mm day -1, during 60 through 84 days after planting, raching a maximum of 5,96 mm day -1, during 84 through 108 days after planting; and decreasing to 4,25mm day -1, during 108 through 115 days after planting