Shoot-Root Interplay Mediates Defoliation-Induced Plant Legacy Effect

Area of Science:

• Ecology
• Plant Biology
• Ecosystem Science

Background:

• Shoot defoliation impacts grassland root traits, potentially affecting ecosystem functioning.
• Reciprocal feedback between shoot and root traits is crucial but experimentally underexplored.

Purpose of the Study:

• Investigate shoot-root reciprocal feedbacks in the perennial grass *Leymus chinensis*.
• Determine how shoot and/or root removal affects plant traits and trait plasticity.

Main Methods:

• Controlled hydroponics experiment with *Leymus chinensis*.
• Treatments included shoot removal, root removal, and combined removal.
• Measured various aboveground and belowground plant traits, including root architecture and photosynthetic traits.

Main Results:

• Under-compensatory growth observed in both shoot defoliation and root severance.
• Defoliation reduced root biomass by 60.11%; root severance reduced shoot biomass by 40.49%.
• Trait plasticity exhibited a sub-additive response, buffering negative impacts and enhancing plant persistence.

Conclusions:

• Trait plasticity is key to shoot-root reciprocal feedbacks and growth persistence in grassland plants.
• Findings inform understanding of grassland resilience and legacy effects.
• Highlights the importance of perennial species' adaptive strategies in changing environments.