Related Experiment Video
Updated: Aug 8, 2026
11:09
Relating Stomatal Conductance to Leaf Functional Traits
Published on: October 12, 2015
Leaf development regulates state transition capacity in trees
Chen Hu1, Sanchali Nanda2,3, Maria Dolores Pissolato2
1Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden. chen.hu@umu.se.
Nature Communications
|August 6, 2026
Summary
State transitions (ST) balance light energy in plants. This study reveals ST capacity declines with leaf age in trees, impacting photosynthesis under dynamic light and highlighting developmental control.
Area of Science:
- Plant Physiology
- Photosynthesis Research
- Molecular Biology
Background:
- State transitions (ST) are crucial for balancing excitation energy between photosystem I and II.
- While well-studied in Arabidopsis, ST regulation and significance in other angiosperms, especially trees, are largely unknown.
Purpose of the Study:
- Investigate ST regulation and physiological significance in hybrid aspen and other tree species.
- Determine the impact of developmental and environmental factors on ST capacity.
- Elucidate the genetic basis and ultrastructural correlates of ST in trees.
Main Methods:
- Physiological measurements (e.g., chlorophyll fluorescence for qT).
- Biochemical analyses (e.g., pigment ratios).
- Ultrastructural examination of thylakoid architecture.
- Genetic analysis using STN7 knockout mutants.
Main Results:
- A significant canopy gradient in ST capacity (qT) was observed, with younger leaves showing higher capacity.
- A conserved developmental decline in qT was found across tree species.
- Reduced qT correlated with increased grana stacking and altered LHCII/PSII ratios, but not LHCII phosphorylation.
- STN7 mutants showed altered PSI/PSII ratios, reduced PSII efficiency in young leaves, and slower growth under variable light.
Conclusions:
- State transitions are developmentally regulated in trees, with capacity declining during leaf maturation.
- Thylakoid architecture remodeling may influence ST-related functional reorganization.
- ST is vital for plant performance under dynamic light conditions, particularly in young leaves.
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