mohammed (2026) Assessing the Impact of Deficit Irrigation Levels on Wheat Growth, Yield, and Water Use Efficiency in Semi-Arid Regions

Identification

• Journal: Muthanna Journal for Agricultural Sciences
• Year: 2026
• Date: 2026-04-06
• Authors: Othman mohammed
• DOI: 10.52113/mjas04/12.2/8

Research Groups

Surveying Engineering Techniques Department, Iraq

Short Summary

This study investigated the impact of four deficit irrigation levels (100%, 80%, 60%, 40% of crop evapotranspiration) on wheat growth, yield, and water use efficiency in a semi-arid region. It found that 80% ETc irrigation maintained comparable yields to full irrigation while significantly improving water use efficiency, making it an optimal strategy for water-limited environments.

Objective

• To assess the impact of varying deficit irrigation levels (100%, 80%, 60%, 40% ETc) on wheat growth, final grain yield, and water use efficiency in a semi-arid region.
• To determine which deficit irrigation level offers the best trade-off between yield and water savings.

Study Configuration

• Spatial Scale: Field experiment in a semi-arid region (likely Iraq, based on author affiliation).
• Temporal Scale: Two consecutive growing seasons.

Methodology and Data

• Models used: Not explicitly stated for data analysis; theoretical frameworks (Crop Water Production Function, Plant-Water Relations, Integrated Water Resources Management) were discussed.
• Data sources: Field observations and measurements (plant height, leaf area index, above-ground biomass, grain yield, water use efficiency, spike length, grains per spike, thousand-grain weight).

Main Results

• Full irrigation (100% ETc) produced the highest grain yield of 6.2 metric tons per hectare (t/ha).
• Moderate deficit irrigation at 80% ETc resulted in a grain yield of 5.9 t/ha (a 4.8% reduction compared to full irrigation) while significantly improving water use efficiency (1.64 kg/m³ compared to 1.38 kg/m³ at 100% ETc).
• Severe water stress (40% ETc) drastically reduced grain yield to 3.8 t/ha (a 38.7% reduction). Although water use efficiency numerically increased to 2.11 kg/m³ at 40% ETc, this came at the cost of substantial yield loss.
• Growth parameters declined with decreasing irrigation: plant height ranged from 0.95 m (100% ETc) to 0.70 m (40% ETc), and above-ground biomass ranged from 0.135 kg/plant (100% ETc) to 0.095 kg/plant (40% ETc).
• Yield components were highly sensitive to water deficit: spike length ranged from 0.105 m (100% ETc) to 0.080 m (40% ETc), grains per spike from 50 to 38, and thousand-grain weight from 0.042 kg to 0.035 kg.
• A strong positive correlation was found between applied water, biomass, and grain yield (r = 0.92, p < 0.01).

Contributions

This study provides region-specific (likely Iraq) optimal deficit irrigation strategies for wheat, demonstrating a practical balance between yield and water conservation in semi-arid environments. It reinforces the understanding of wheat's physiological response to water stress and offers actionable recommendations for sustainable water management in water-scarce regions.

Funding

Not explicitly stated in the provided text.

Citation

@article{mohammed2026Assessing,
  author = {mohammed, Othman},
  title = {Assessing the Impact of Deficit Irrigation Levels on Wheat Growth, Yield, and Water Use Efficiency in Semi-Arid Regions},
  journal = {Muthanna Journal for Agricultural Sciences},
  year = {2026},
  doi = {10.52113/mjas04/12.2/8},
  url = {https://doi.org/10.52113/mjas04/12.2/8}
}