ABSTRACT Plant yield is strongly influenced by the amount of water used by it. In this sense, yield response factor (Ky) allows evaluating the decrease in yield as a function of the evapotranspiration that occurs, which may be an important tool for harvest forecasting. Therefore, this study aimed to determine Ky for winter corn crop grown in the region of Dourados, MS, Brazil. The yield function analysis based on the water factor, which requires actual (Ya) and maximum (Ym) yield data, as well as actual (ETa) and maximum (ETm) evapotranspiration, was used to adjust Ky. Ym was assumed to be 8,820 kg ha−1, while Ya was obtained for each season from the database SIDRA from IBGE. ETm and ETa were estimated by sequential daily water balance, considering four... |