Active shape control by plants in dynamic environments.

Area of Science:

• Plant biology
• Biophysics
• Mechanobiology

Background:

• Plants exhibit active shape control in response to external stimuli like gravity and internal stimuli like proprioception.
• Rotation, such as in a rotating clinostat, modulates these responses, leading to complex plant shapes.
• Understanding these dynamics is crucial for comprehending plant development and active materials.

Purpose of the Study:

• To investigate the response of a growing plant to gravity and rotation using a rod model.
• To analyze the combined effects of external (gravity) and internal (proprioception) stimuli on plant shape.
• To explore the resulting three-dimensional dynamics and behaviors.

Main Methods:

• Utilized a previously derived rod model to simulate plant growth and response.
• Analyzed plant behavior under varying rotation speeds (clinostat experiments).
• Investigated the influence of axial growth on plant dynamics.

Main Results:

• In the absence of rotation, plants converge to a universal planar shape.
• Rotation induces stable, three-dimensional dynamic equilibria where the plant axis remains fixed.
• Axial growth leads to steady behaviors, including solitary wave formation.

Conclusions:

• Plant shape control is a complex interplay of external and internal stimuli.
• The study provides insights into the out-of-equilibrium dynamics of plants in three dimensions.
• Internal stimuli are critical for robust shape control in active materials like plants.