Multi-Level Approaches for Assessing Molecular and Physiological Traits of Drought and Heat Stress Tolerance in Plant Reproductive Development.

Abiotic stress, particularly heat and drought, significantly impacts plant reproductive development, threatening crop productivity and food security. Understanding stress tolerance mechanisms requires a multi-level approach that integrates physiological, biochemical, and molecular traits in different experimental settings. This review explores key methodologies for assessing resilience to single and combined abiotic stress in reproductive tissues, from growth chamber experiments to greenhouse and field trials. Essential physiological and biochemical traits indicative of stress responses are highlighted alongside molecular pathways that provide deeper insights into adaptation to drought and heat stress. The use of multi-omics techniques, including transcriptomics, proteomics, and metabolomics, as powerful tools for identifying novel stress-associated traits is discussed, with an emphasis on the integration of these techniques into a holistic framework, which also incorporates single-cell approaches. Finally, we address the limitations of the current methodologies and propose future research directions to improve stress resilience assessment in plant reproductive development.