Plant Stress Tolerance Mechanisms to Drought and Salinity

Plants exposed to water deficit or high salinity deploy a suite of integrated responses that span morphological, physiological, biochemical and molecular levels. Morphological adjustments include enhanced root growth, reduced leaf area and cuticle thickening to limit water loss. At the cellular level, osmotic adjustment through accumulation of compatible solutes such as proline and glycine betaine maintains cell turgour, while ion transporters and compartmentalisation mechanisms ensure ion homeostasis under saline conditions. Stress perception triggers abscisic acid–mediated signalling cascades, activating stress‐responsive transcription factors and genes encoding late embryogenesis abundant proteins, aquaporins and antioxidant enzymes. Reactive oxygen species generated under stress are scavenged by superoxide dismutase, catalase and peroxidases to prevent oxidative damage. Together, these mechanisms allow both glycophytic crops and naturally salt‐tolerant halophytes to survive and maintain productivity under challenging environments. Advances in genomics and phenotyping are accelerating the identification of key tolerance traits for breeding and biotechnological interventions, offering routes to enhance global food security amid climate change.

Research from Nature Portfolio

Studies of a salt‐adapted halophyte examined four inland populations of Salicornia europaea across a salinity gradient up to 1,000 mM NaCl. Results revealed population‐specific tolerance mechanisms: differences in antioxidative enzyme activities, ion accumulation patterns and morphological traits were linked to the local environment. One population exhibited exceptionally high root catalase activity under extreme salinity, correlating with superior biomass retention. These findings emphasise that intra‐species variation can inform selection of superior genotypes for saline agriculture, restoration of degraded soils and exploration of halophytes as functional crops.

Plant Stress Tolerance Mechanisms to Drought and Salinity publication trend

The graph below shows the total number of articles in plant stress tolerance mechanisms to drought and salinity across all publications each year (not limited to Nature Index journals).

Technical terms

Osmotic adjustment: Cellular accumulation of solutes to maintain water uptake and turgour under stress.

Reactive oxygen species (ROS): Highly reactive molecules generated during stress that can damage proteins, lipids and nucleic acids.

Halophyte: Plant species naturally adapted to grow in high‐salinity environments.

Compatible solute (osmolyte): Small organic molecule such as proline that balances cellular osmotic pressure without interfering with metabolism.

Antioxidant enzymes: Proteins (e.g. superoxide dismutase, catalase) that detoxify ROS to protect cellular structures.

Abscisic acid (ABA): Plant hormone central to stress signalling, regulating stomatal closure and gene expression.

References

1. Comprehensive assessment to reveal the salt tolerance potential of cultivated eggplants and their wild relatives. Frontiers in Plant Science (2025).
2. Growth and antioxidant responses to water stress in eggplant MAGIC population parents, F1 hybrids and a subset of recombinant inbred lines. BMC Plant Biology (2024).
3. Exogenous citric acid improves growth and yield by concerted modulation of antioxidant defense system in brinjal (Solanum melongena L.) under salt-stress. Journal of King Saud University - Science (2024).
4. The local environment influences salt tolerance differently in four Salicornia europaea L. inland populations. Scientific Reports (2025).