Evaluation of Crop Water Production Functions (CWPF) for Carrot from a Mathematical Modeling Perspective

Source abstract

Crop water production functions (CWPF), which define the functional relationship between yield and water use in agricultural production, assuming all other production input variables remain constant, are of great importance in defining different irrigation strategies and determining optimal irrigation levels. The aim of this study is to estimate yield in carrot by utilizing the performance of the Stewart, Jensen, Minhas, Blank, and Rao functions (CWPF). Field studies on carrot were conducted in 2019 and 2020 at the Agricultural Production Center of Bursa Uludağ University Bursa Yenişehir Vocational School. The water stress sensitivity indices of crop water production functions (CWPF) were determined using ET and yield values from the first year. The yield values simulated with the crop water production functions in 2019 were compared with the yield values measured in the field in 2020. Using five different crop water production models (CWPF), the water sensitivity indices of carrot at four different crop growth stages were determined. Based on the water sensitivity indices of carrot during four different crop growth periods, the yield formation period (Y) was determined to be the most water-sensitive period. The yield formation (Y) period was followed by the flowering (F) and vegetative (V) periods. The stage at which carrot is least sensitive to water is the ripening (R) stage. When comparing the water stress sensitivity indices calculated for four different crop growth stages of carrot, it can be said that the estimates obtained from the Rao and Blank (Bras-Cordova) models are more accurate and, therefore, are the most suitable models to be recommended within crop water production functions.