Plant Adaptation to Drought Stress: The Role of Anatomical and Morphological Characteristics in Maintaining the Water Status

Aridity, characterized by a prolonged and natural imbalance in water availability, results in reduced soil moisture, which directly affects plant distribution and limits crop productivity. Plants subjected to drought stress exhibit morpho-anatomical changes that are closely associated with cellular, physiological, and biochemical adaptations aimed at minimizing water loss through transpiration and optimizing water-use efficiency. Understanding these mechanisms is critical for developing drought-tolerant crop varieties. This review describes both short-term and long-term morpho-anatomical adaptations that help stabilize shoot water potential, providing valuable insights for breeding programs aimed at enhancing drought resilience. Specifically, it discusses the significance of modifications in stem, trunk, and branch morphology, which play a pivotal role in improving water retention and hydraulic conductivity across diverse plant species. The degree of isohydry or anisohydry in plant hydraulic strategies is also examined, as it is crucial for predicting plant responses to drought conditions induced by climate change. By identifying key morpho-anatomical traits, this review highlights their importance in developing plant varieties suited for re-vegetating drought-affected areas. These traits are vital for devising long-term strategies to mitigate the impact of severe droughts by promoting the cultivation of drought-tolerant plants. Future research should prioritize strengthening the links between vascular morpho-anatomical traits and agricultural practices under stress conditions to improve crop growth and yield under drought stress.