The aim of this work was to evaluate the influence of water deficit and photoperiod on the development and in the grain yield of soybean, at three sowing times (October 15th , November 15th and December 15th ) in Dourados, Mato Grosso do Sul State, Brazil. The work was based on meteorological data of 20 years. The soybean water deficiency was calculated through a daily sequential water balance. The photoperiod was determined through the latitude and the date. The water deficit decreased with the sowing time delay. Based on water deficit and photoperiod, the soybean sowing time in Dourados should be in November.
Glycine max; water balance; water stress
