When wuthering winds create fluttering fields: structural and biomechanical properties determine canopy light fluctuation properties of 10 wheat cultivars.

Wind-driven plant movement generates rapid light fluctuations (windflecks), which can impact canopy photosynthesis. Targeting crop photosynthesis in dynamic light provides a potential path towards boosting yield. Here, we quantified how plant architecture and biomechanics modulate such windflecks across 10 high-yielding cultivars of winter wheat (Triticum aestivum). Using synchronized high-frequency measurements of irradiance, wind speed, and canopy motion (quantified by frame differencing from video), we assessed the propensity of wheat cultivars to move (motion sensitivity), and the ability for movement to produce windflecks (light modulation efficiency) in the field. There was up to 10-fold variation in the quantity of motion between cultivars under identical wind speeds. Cultivars also exhibited structural trade-offs and specific in canopy windfleck properties. Some had low motion under wind but produced frequent windflecks when moving, whereas others exhibited high motion under similar wind but varied in windfleck frequency. Overall, windfleck properties were best explained by aerodynamic traits: cultivars with narrower leaves and lower leaf-to-stem mass ratios were associated with more intense windflecks. These findings establish that wheat cultivars actively modulate their light environment through biomechanical traits. By integrating plant motion into crop models, favouring motion-light relationships, which could provide a critical route to yield improvements in turbulent environments.