Ai et al. (2026) Stage-specific soil moisture regulation improves grain yield and water productivity of drip-irrigated winter wheat: Associations with stem carbohydrate dynamics and grain filling

Identification

• Journal: Agricultural Water Management
• Year: 2026
• Date: 2026-09-19
• Authors: Pengrui Ai, Ying Zhang, Wei Qiang, Yingjie Ma, Qiuping Fu
• DOI: 10.1016/j.agwat.2026.110802

Research Groups

• College of Hydraulic and Civil Engineering, Xinjiang Agricultural University
• Xinjiang Water Conservancy Project Safety and Water Disaster Prevention Key Laboratory

Short Summary

This study investigated the effects of stage-specific soil moisture regulation on wheat growth, photosynthesis, yield formation, grain quality, and water productivity under drip irrigation in arid conditions. The results showed that using a higher irrigation-initiation threshold during reproductive growth was associated with sustained photosynthetic performance, more favorable stem carbohydrate dynamics, and improved grain accumulation.

Objective

• Determine the stage-specific effects of soil-moisture regulation on wheat growth, photosynthesis, yield formation, grain quality, and water productivity.
• Characterize organ-specific carbohydrate dynamics and assess their predictive associations with grain dry-matter accumulation.
• Examine the temporal relationships among photosynthetic activity, apparent stem reserve depletion, and grain dry-matter accumulation during grain filling.

Study Configuration

• Spatial Scale: Field experiment conducted at a single location in Xinjiang, China.
• Temporal Scale: Three growing seasons (2022–2023, 2023–2024, and 2024–2025).

Methodology and Data

• Models used: Random forest regression for predictive associations between organ-specific carbon-related traits and grain dry-matter accumulation.
• Data sources: Field measurements of soil moisture, photosynthetic characteristics, aboveground dry matter, key enzymes involved in carbohydrate synthesis, sucrose and starch content, yield and its components, evapotranspiration (ET), water productivity (WP), and processing quality.

Main Results

• Stage-specific soil moisture regulation had significant effects on wheat growth, photosynthesis, yield formation, grain quality, and water productivity.
• Using a higher irrigation-initiation threshold during reproductive growth was associated with sustained photosynthetic performance, more favorable stem carbohydrate dynamics, and improved grain accumulation.
• The ratio of net stem dry matter (DM) decline during grain filling to final grain DM ranged from 14.36% to 25.04%.
• Random forest regression analysis showed that sucrose content in stems had the highest predictive importance for grain dry-matter accumulation.

Contributions

• This study provides a physiological basis for improving wheat productivity and water use under arid conditions by optimizing irrigation timing.
• The findings suggest that stage-specific soil moisture regulation can improve wheat growth, photosynthesis, yield formation, and water productivity.

Funding

• Supported by the Xinjiang Water Conservancy Project Safety and Water Disaster Prevention Key Laboratory.

Citation

@article{Ai2026Stagespecific,
  author = {Ai, Pengrui and Zhang, Ying and Qiang, Wei and Ma, Yingjie and Fu, Qiuping},
  title = {Stage-specific soil moisture regulation improves grain yield and water productivity of drip-irrigated winter wheat: Associations with stem carbohydrate dynamics and grain filling},
  journal = {Agricultural Water Management},
  year = {2026},
  doi = {10.1016/j.agwat.2026.110802},
  url = {https://doi.org/10.1016/j.agwat.2026.110802}
}