Does greater specific leaf area plasticity help plants to maintain a high performance when shaded?

Area of Science:

• Plant Ecology
• Evolutionary Biology
• Physiology

Background:

• Phenotypic plasticity is assumed to enhance plant environmental tolerance and fitness homeostasis.
• Shade-induced increases in specific leaf area (SLA) are widely considered adaptive for optimizing light capture.
• The adaptive nature of SLA plasticity has rarely been empirically tested.

Purpose of the Study:

• To determine if SLA plasticity contributes to maintaining plant biomass under shaded conditions.
• To investigate the relationship between SLA plasticity and biomass homeostasis in plants.

Main Methods:

• A meta-analytical approach was used.
• Data from 280 species across 467 studies were analyzed.

Main Results:

• Plants increased SLA by 55.4% and decreased biomass by 59.9% under shade.
• Species with higher baseline SLA maintained biomass better under shade.
• Greater SLA plasticity was negatively correlated with biomass maintenance under shade.

Conclusions:

• While high SLA itself aids biomass homeostasis, SLA plasticity does not appear to contribute to it.
• Plastic changes in SLA may be passive or by-products of other adaptive responses, not adaptive themselves.