Validation of AquaCrop for Deficit Irrigation on Garlic (Allium sativum L.) for Semi-arid Conditions

Impact of various irrigation regimes on agricultural yield can be assessed with use of crop water productivity models. Agricultural water productivity model called AquaCrop has been adopted by FAO's Land and Water Division in 2009. It’s especially appropriate for situations like semi-arid regions, where water isamajor agricultural production constraint, and it replicates the yield response to water for herbaceous crops. Calibration of AquaCrop model for several irrigation regimes for garlic (Allium sativumL.) was the aim of this work to ascertain the impact of these regimes on crop growth and yield parameters. A randomised block design field experiment with 3 replications has been carried out at Mahatma PhuleKrishi Vidya peeth in Rahuri, Maharashtra, during 2021–2022 rabi season. The experiment included 27 treatment combinations applied at different growth stages of garlic: vegetative stage, bulb initiation, and bulb development stage.According to the results, there was no discernible difference in yield.The maximum simulated yield obtained in Treatment (T1­) was 8.08 t ha-1, and lowest yield obtained 4.69 t ha-1 in treatment T27. Maximum simulated evapotranspiration was recorded in treatment (T2, was 363.5 mm, and lowest, 239.6 was recorded in treatment T27. Garlic's crop production and evapotranspiration water productivity were accurately reproduced by the AquaCrop model. The AquaCrop model can be utilised to simulate CWR of bulb crops, including garlic, according to validation utilizing Nash-Sutcliffe efficiency (E), RMSE (root mean square error),index of agreement (d).