Plant mating systems affect adaptive plasticity in response to herbivory

Area of Science:

• Plant biology
• Ecology
• Evolutionary biology

Background:

• Mating system variation, particularly inbreeding, has well-studied fitness consequences.
• Ecological consequences of inbreeding in plants are less understood.
• Plants exhibit adaptive phenotypic plasticity in response to ecological stresses like herbivory.

Purpose of the Study:

• To investigate the effects of experimental inbreeding on phenotypic plasticity in resistance and growth traits in Solanum carolinense.
• To determine if inbreeding impacts the regulation of defense and growth under stress.

Main Methods:

• Experimental inbreeding was applied to Solanum carolinense.
• Plants were subjected to damage to assess resistance and growth (tolerance) trait responses.
• Phytohormone levels (abscisic acid, indole acetic acid, jasmonic acid) were measured.

Main Results:

• Inbreeding reduced the ability of plants to increase resistance traits after damage.
• Inbreeding disrupted growth trait adjustments in response to damage, suggesting deleterious mutations.
• Production and wound-induced upregulation of key phytohormones were significantly reduced under inbreeding.

Conclusions:

• Inbreeding negatively affects the plasticity of induced responses in plants.
• Phytohormonal pathways are implicated in mediating the negative effects of inbreeding on plant defense and growth.
• These findings have implications for fragmented plant populations facing mate limitation and environmental change.