Physiological and Molecular Bases of Drought and Heat Tolerance: Harnessing Genetic Diversity for Climate Resilience in Plants

Climate change is intensifying the frequency, duration, and severity of drought and heat events, placing plant performance, ecosystem stability, and global food security under unprecedented pressure. Plants respond to these stresses through a tightly coordinated network of physiological and molecular processes — from stomatal and hydraulic regulation to photosynthetic adjustment, osmotic and redox homeostasis, and hormone-mediated signaling. The capacity to mount and sustain these responses varies widely across genotypes, and the genetic diversity present within and among species represents a vast, largely untapped reservoir of adaptive variation. Yet the mechanisms that translate this diversity into measurable differences in stress tolerance remain incompletely understood, limiting our ability to explain why some genotypes thrive under stress while others fail.Bridging this gap requires moving beyond cataloguing genetic variation toward a mechanistic understanding of how that variation shapes plant function under stress. Advances in high-throughput phenotyping, multi-omics integration, and physiological modeling now make it possible to connect genotypic differences to specific physiological traits and to the molecular pathways that govern them. By using natural, induced, and wild-relative diversity as a lens, researchers can dissect the regulatory networks that underpin drought and heat tolerance and identify the physiological signatures most relevant to resilience in real environments.This Research Topic aims to advance our understanding of the physiological and molecular mechanisms underlying drought and heat tolerance, using genetic diversity as a framework to dissect adaptive trait variation across model species, crops, and their wild relatives. We particularly welcome studies that link genotypic variation to physiological function, that integrate scales from the molecular to the whole-plant and canopy level, and that consider combined and fluctuating stresses representative of field conditions. We welcome contributions including:- Physiological characterization of contrasting genotypes and germplasm under drought and heat stress- Stomatal and hydraulic regulation and water-use efficiency- Photosynthetic and metabolic acclimation to abiotic stress- Osmotic adjustment, membrane and protein stabilization, and antioxidant responses- Hormonal and molecular signaling networks in stress responses- Root-system physiology and below-ground adaptation to water and heat stress- Responses to combined and fluctuating drought and heat stress- Multi-omics and high-throughput phenotyping approaches linking physiological traits to genetic variationTogether, these contributions will help build an integrated, mechanistic picture of how genetic diversity sustains plant resilience, providing a physiological foundation that can ultimately inform efforts to safeguard productivity under a changing climate. We invite Original Research, Reviews, Mini-Reviews, Methods, and Perspectives. Topic editors: Cándido López-Castañeda Source: https://www.frontiersin.org/research-topics/82797/physiological-and-molecular-bases-of-drought-and-heat-tolerance-harnessing-genetic-diversity-for-climate-resilience-in-plants