Pachore et al. (2025) Validation of AquaCrop for Deficit Irrigation on Garlic (Allium sativum L.) for Semi-arid Conditions

Identification

• Journal: Current Agriculture Research Journal
• Year: 2025
• Date: 2025-09-08
• Authors: R.A. Pachore, S. K. Dingre, M. S. Mane, Mahesh R Patil
• DOI: 10.12944/carj.13.2.14

Research Groups

• Department of Irrigation and Drainage Engineering, Mahatma Phule Krishi Vidyapeeth, Rahuri, Ahmednagar, Maharashtra, India
• Department of Irrigation and Drainage Engineering, Dr. Annasaheb Shinde College of Agricultural Engineering and Technology, Mahatma Phule Krishi Vidyapeeth, Rahuri, Ahilyanagar, Maharashtra, India
• College of Agriculture, Pune, Mahatma Phule Krishi Vidyapeeth, Rahur, Maharashtra, India
• Department of Statistics, Post Graduate Institute, Mahatma Phule Krishi Vidyapeeth, Rahuri, Ahilyanagar, Maharashtra, India

Short Summary

This study calibrated and validated the AquaCrop model for simulating garlic yield and evapotranspiration water productivity under various deficit irrigation regimes in semi-arid conditions, demonstrating its applicability for bulb crops. The model accurately reproduced crop production and water productivity, with variations potentially linked to crop structure and phenology.

Objective

• To calibrate and validate the AquaCrop model for simulating garlic (Allium sativum L.) yield, growth, and water-use characteristics under varying deficit irrigation regimes in semi-arid conditions.

Study Configuration

• Spatial Scale: Field experiment conducted at Mahatma Phule Krishi Vidyapeeth, Rahuri, Maharashtra, India (19°48′ N to 19°57′ N latitude, 74°32′ E to 76°19′ E longitude, 657 meters above mean sea level) with a semi-arid climate.
• Temporal Scale: Rabi season, from 19 December 2021 to 26 April 2022.

Methodology and Data

• Models used: AquaCrop model (FAO's Land and Water Division) for crop simulation; Penman-Monteith equation for reference evapotranspiration calculation.
• Data sources:
  • Field Experiment: Randomized block design with 27 treatment combinations (varying water stress levels: 0%, 30%, 60% at vegetative, bulb initiation, and bulb development stages) and 3 replications. Drip irrigation system used.
  • Climatic Data: Daily maximum and minimum sunshine, air temperatures, relative humidity, rainfall, wind speed, and evaporation collected from the meteorological observatory of Mahatma Phule Krishi Vidyapeeth, Rahuri.
  • Soil Data: Soil texture (heavy clay) and soil depth.
  • Agronomic Data: Observed garlic yield (t ha⁻¹), actual evapotranspiration (mm), and evapotranspiration water productivity (t ha⁻¹ mm⁻¹).
  • Statistical Analysis: Analysis of Variance (ANOVA), Nash-Sutcliffe efficiency (E), Root Mean Square Error (RMSE), and Index of Agreement (d) were used for model performance evaluation.

Main Results

• Observed evapotranspiration water productivity (ETWP) for garlic ranged from 0.022 to 0.025 t ha⁻¹ mm⁻¹, with the highest values in no/low water stress treatments and the lowest in high water stress treatments.
• The AquaCrop model simulated maximum yield of 8.08 t ha⁻¹ (no stress, T1) and lowest yield of 4.69 t ha⁻¹ (high stress, T27).
• Deviation between simulated and actual crop yields ranged from -18.26% to 3.47%.
• Maximum simulated evapotranspiration was 363.5 mm (T2), and the lowest was 239.6 mm (T27).
• Model validation for yield showed a Nash-Sutcliffe efficiency (E) of -0.035, RMSE of 0.57 t ha⁻¹, and an Index of Agreement (d) of 0.83, indicating a good fit.
• Model validation for evapotranspiration water productivity showed an E of -3.65, RMSE of 38.44 kg m⁻³, and a d of 0.483, indicating a fair fit.
• Variations in model outcomes were suggested to be influenced by crop structure and phenology rather than solely climate, soil, and water supply conditions.

Contributions

• First-time calibration and validation of the AquaCrop model specifically for garlic (Allium sativum L.) under deficit irrigation in semi-arid conditions of Maharashtra, India.
• Demonstrates the AquaCrop model's capability to simulate crop production and evapotranspiration water productivity for bulb crops, providing a valuable tool for water management.
• Provides a framework for optimizing irrigation strategies by integrating economic, environmental, and productive aspects of agricultural systems.
• Highlights the need for further consideration of crop structure and phenology to enhance the accuracy of water productivity models for belowground stem and bulb-like crops.

Funding

• Chatrapati Shahu Maharaj National Research Fellowship (SARTHI), Pune.
• Grant number: Go. No./Sarthi/Scholarship/CSMNRF-2021/2021-22/896.

Citation

@article{Pachore2025Validation,
  author = {Pachore, R.A. and Dingre, S. K. and Mane, M. S. and Patil, Mahesh R},
  title = {Validation of AquaCrop for Deficit Irrigation on Garlic (Allium sativum L.) for Semi-arid Conditions},
  journal = {Current Agriculture Research Journal},
  year = {2025},
  doi = {10.12944/carj.13.2.14},
  url = {https://doi.org/10.12944/carj.13.2.14}
}