Jump to Main Content
Enhancing field scale water productivity for several rice cultivars under limited water supply
- Jonubi, Roza, Rezaverdinejad, Vahid, Salemi, Hamidreza
- Paddy and water environment 2018 v.16 no.1 pp. 125-141
- crop production, cultivars, deficit irrigation, drying, experimental design, field experimentation, irrigation management, irrigation water, model validation, models, paddies, rice, water supply, Iran
- Rice production is one of the largest consumer of water in agriculture. In general, the irrigation water productivity (WPI) is low in paddy fields. In order to improve WPI, a field experiment was conducted in central of Iran during 2009–2010. The experiment was consisted of three irrigation managements and eight advanced rice cultivars (Gerdeh (V ₁), Zayande-roud (V ₂), Sazandegi (V ₃), Hasani (V ₄), 67–97 (V ₅), 67–113 (V ₆), 67–47 (V ₇), and 67–72 (V ₈)) in a split plot design with three replications. The irrigation treatments were I ₁ and I ₂: permanent flooding under 3.5 and 2.2 cm water depth, respectively, and I ₃: 0–1.5 cm alternative wetting and drying. To explore deficit irrigation for improved WPI, SWAP model was calibrated using intensive measured data for the foregoing years. The average normalized root-mean-square deviation of yield during calibration was 0.03% and during validation was 4.94% indicating acceptable calibration and validation of the model. WPI for all cultivars were enhanced up to 61% by applying 50% deficit irrigation. On this irrigation regime, V ₂ and V ₆ provided the highest WPI (0.84 and 0.79 kg m⁻³, respectively) whereas V ₄ and V ₈ yielded the lowest (0.50 and 0.57 kg m⁻³, respectively). The results indicated that rice cultivars (V ₂ and V ₆) are the best option with the highest WPI in the irrigation district and calibrated model was able to effectively simulate the crop growth under water deficit conditions.