The objective of this work was to evaluate hydric relations and the performance of simplified and agrometeorological models to estimate the productivity of wheat crop, considering four tillage soil systems, in Ponta Grossa, Parana State. The soil type at the experimental area has been classified as Typic Hapludox and the climate of the region classified as Cfb type, according to Köppen climatic classification. The yield data of wheat crop (five seasons) and meteorological were supplied by the ABC Foundation and SIMEPAR, respectively. The tested models are based on the crop yield potential and the ER/ETc relation (actual / crop evapotranspiration), determined by daily water balance occurred during different growth stages. The reference evapotranspiration (ETo) was estimated by the Penman-Monteith method. Considering the numerous tests carried out, the Jensen model show the best estimates of productivity, using yield response factor obtained by multiple regression.
Crops planning; Triticum aestivum; water balance
