FERTIRRIGERE: a simple tool-model for managing water and nutrient supply in drip-irrigated processing tomatoes

Based on the models developed during the EU Qualitom project (Irrigere V1.1 and V2.01, Fertiliz), a new integrated model was built which introduces greater flexibility at the input level while improving the model output precision at the field level. The model automatically estimates missing climate figures or chooses the most precise equation to calculate ET 0 using available inputs. A variety database allows the growth stages and the yield forecast to be easily managed and thus improves irrigation and fertigation strategy management. Pedotransfer functions were implemented. The irrigation threshold smoothing function was upgraded. The plant stress coefficient (Ks) was changed to remedy its poor sensitivity. Water balance and nutrient balances were assessed on the basis of daily root growth and the organic matter mineralisation rate was calculated using two different options. Plant nutrient uptake curves were revised. The model was successfully tested in Italy jointly with the Tomato Growers Association and Tomato Industries extension services.