Water use efficiency in cereal crops: stomatal, hydraulic, biochemical mechanisms, and translational strategies for improvement.

Water use efficiency in cereal crops is primarily governed by complex molecular and physiological mechanisms, with key targets like EPFL-ERECTA and H+-ATPase pathways showing strong cereal-specific support.

• Why it matters: Improving water use efficiency is critical for increasing cereal yields under water-limited conditions, yet a comprehensive mechanistic framework integrating molecular, physiological, and genetic factors has been lacking.
• What they did: The review synthesizes knowledge across multiple scales, examining stomatal regulation, mesophyll conductance, root hydraulics, and genetic targets, highlighting 5 research priorities to translate understanding into field improvements.
• The result: This integrated framework enables targeted strategies for enhancing WUE, emphasizing the importance of specific genetic pathways and physiological processes, and guiding future research toward practical, field-level gains.