Research Progress in Plant Beneficial Fungi-Mediated Alleviation of Drought Stress in Crops

Climate change has emerged as a major global concern and has substantially intensified the occurrence of abiotic stresses in plants. Among the abiotic constraints limiting crop production, drought stress is regarded as one of the most severe and pervasive challenges. To this end, developing efficient and sustainable strategies to mitigate drought has become an urgent priority in agricultural research. Current approaches to improving drought tolerance mainly include optimizing irrigation management, applying chemical regulators, and breeding drought-resistant cultivars. However, these strategies often suffer from high input costs, limited durability of effects, potential environmental risks, or restricted regional applicability, making it difficult to achieve long-term and stable drought mitigation. In recent years, a growing body of evidence has indicated that rhizosphere microorganisms play pivotal regulatory roles in plant drought adaptation, with beneficial fungi being particularly important. Nonetheless, the key processes and mechanisms by which microbiomes mediate crop adaptation to drought need to be elucidated systematically. In this review, we synthesize recent advances in the field and, against the backdrop of increasingly severe global drought, summarize the major impacts of drought stress on crop growth and physiological processes. We further systematically synthesize the key mechanisms by which beneficial fungi alleviate drought stress in crops. Finally, we outline future research directions to deepen our understanding of rhizosphere-crop-microbe interaction networks and to provide a theoretical basis for developing beneficial fungus-centered microbial biofertilizers and microbiome-mediated strategies to enhance crop drought resilience.