Combining yield potential and drought resilience in a spring wheat diversity panel

Area of Science:

• Agricultural Science
• Plant Biology
• Genetics

Background:

• Increasing global population and climate change necessitate higher-yielding, resilient crops, especially against drought.
• Spring wheat is a vital global crop, but its yield is threatened by water scarcity.
• Developing drought-resilient wheat varieties is essential for sustainable agriculture.

Purpose of the Study:

• To identify spring wheat lines combining high yield potential with drought resilience.
• To evaluate wheat performance under intermittent drought stress at different developmental stages.
• To understand the relationship between physiological traits and yield under drought.

Main Methods:

• A spring wheat diversity panel of 150 lines was evaluated under fully irrigated and two drought stress conditions (jointing and anthesis stages).
• Drought was imposed for 10 days during critical growth phases in Obregon, Mexico.
• Grain yield, grain number, grain size, leaf relative water content, proline, and leaf sugars were measured.

Main Results:

• Both drought treatments significantly reduced grain number compared to irrigated conditions.
• Drought at jointing primarily affected grain number, while drought at anthesis impacted grain size.
• While most lines performed well in only one environment, 28 lines showed resilience across two conditions, and only three lines were high-yielding across all three environments.
• High grain number was a key trait associated with yield under well-watered and jointing-drought conditions.
• Leaf relative water content did not correlate with yield; proline showed a negative correlation, while leaf sugars had a minor positive correlation.

Conclusions:

• High grain number is a critical trait for maintaining spring wheat yield under drought stress, particularly when stress occurs early in development.
• Identifying and utilizing wheat lines with consistent high yield and resilience across multiple environments is possible.
• This research provides valuable genetic resources and insights into mechanisms for breeding drought-resilient wheat with improved yield potential.