Unveiling the Role of Root Exudates in Plant Adaptation to Drought and Heat Stress

Abstract

Drought and heat are recognized as the foremost abiotic stresses influencing plant growth and yield. In response to stressful conditions, plants undergo various physiological and biochemical modifications to enhance their resilience. Among these modifications, root exudates, comprising a diverse range of organic compounds, significantly impact plant resilience to drought and heat stresses. The soil microbiome plays a crucial role in mitigating drought and heat stress by enhancing plant resilience through various mechanisms, including nutrient acquisition, hormone production, and stress signal modulation. Its interaction with root exudates further amplifies these effects, as root exudates serve as key mediators in shaping microbial communities and promoting beneficial interactions. This review enunciates the crucial role of root exudates in conferring drought and heat stress tolerance, offering novel insights into the mechanisms, root structural changes, and physiological and biochemical adaptations. The role of microorganisms and their interaction with root exudates are explored to unveil the intricate network of interactions orchestrated by root exudates in stress adaptation, mitigation and resilience. In addition, this review examines the various physiological, abiotic, and biotic factors that impact the composition and dynamics of root exudates. Deciphering the complex interactions among these elements is essential to understanding the intricacies of plant stress responses. Furthermore, root exudate extraction techniques are briefed. Overall, this review aims to better understand and drive future research focused on integrating the role of root exudates, soil microbiome for improving adaptation, mitigation and resilience of crops to abiotic stresses such as drought and heat.