High-elevation angiosperms maintain extensive living storage tissue with large non-structural carbohydrate pools

Area of Science:

• Plant physiology
• Ecology
• Alpine botany

Background:

• Extreme elevation survival relies on cellular carbon and nutrient storage.
• High-mountain plants are predicted to have large non-structural carbohydrate (NSC) pools and storage tissue for stress tolerance.
• Comparative data across diverse high-elevation floras is limited.

Purpose of the Study:

• To investigate if high-mountain plants in the western Himalayas increase NSC pools and storage tissue proportion with elevation.
• To examine the relationship between elevation, plant anatomy, and biochemical composition.

Main Methods:

• Analyzed 323 herbaceous species from the western Himalayas (2,650–6,150 m).
• Examined storage organs anatomically and chemically for parenchyma, lignified tissue, soluble sugars, fructans, starch, nitrogen, and phosphorus.
• Used phylogenetically informed models to assess relationships between elevation, tissue anatomy, plant height, and biochemistry.

Main Results:

• Elevation positively correlated with NSC and nutrient concentrations.
• Increased storage pools were linked to expanded parenchyma at the expense of lignified tissue.
• Soluble sugars and fructans, not starch, predicted parenchyma abundance and tracked elevation.

Conclusions:

• Coordinated anatomical and physiological shifts demonstrate a physiology-to-anatomy linkage in alpine plants.
• Elevation-driven accumulation of reserves expands storage cells, enhancing cryoprotection and metabolic buffering.
• This study reveals a widespread mechanism of alpine adaptation linked to storage physiology and tissue architecture.