Wheat Functional Traits and Photosynthetic Responses to Dynamic Shading in Agrivoltaic Systems

Area of Science:

• Agricultural science
• Plant physiology
• Renewable energy integration

Background:

• Growing demand for food and energy necessitates agrivoltaic systems.
• Understanding crop physiological responses to agrivoltaics is crucial but limited.
• Dynamic shading from solar trackers presents unique challenges for crop growth.

Purpose of the Study:

• Investigate the impact of dynamic shading from biaxial solar trackers on wheat photosynthesis and functional traits.
• Analyze leaf-level traits and plant morphology under agrivoltaic conditions.
• Determine wheat's physiological and morphological acclimation to shade.

Main Methods:

• Conducted field studies over two years across eight sites in western France.
• Measured nine leaf-level traits (carbon/nitrogen economy), plant height, and density.
• Analyzed trait responses against 14 environmental and management variables, including received radiation.

Main Results:

• Received radiation significantly reduced CO2 assimilation, respiration, and photosynthetic nitrogen use efficiency (PNUE).
• Limited changes in air/soil temperature and relative humidity were observed.
• Wheat showed minimal morphological acclimation; specific leaf area (SLA) and light compensation point (LCP) were unchanged.
• Chlorophyll content and leaf nitrogen increased, but insufficient to maintain photosynthetic rates.

Conclusions:

• Wheat exhibits limited structural plasticity to intermittent, heterogeneous shade from elevated agrivoltaic systems.
• Elevated, mobile photovoltaic systems differ significantly from ground-mounted installations.
• Varietal selection for agrivoltaics should focus on traits for photosynthetic induction and nitrogen efficiency under fluctuating light.