Unearthing the secrets of drought-driven root system architecture: Nutrient acquisition and rhizosphere microbe interplay

Abstract

Drought, a climatic occurrence that cyclically affects all climatic regions, is more prevalent in tropical and subtropical areas. This phenomenon inflicts physiological harm upon plants within ecosystems and agroecosystems. Apart from the direct scarcity of water, which severely impairs plant development and productivity, there can be consequential issues related to mineral nutrition. These secondary effects can arise and further impact plant development. Amidst drought conditions, roots play a critical role in shaping the growth and development of plants. During these circumstances, our understanding of the molecular mechanisms governing critical responses and interactions between plant roots and their surrounding rhizosphere is less comprehensive in comparison to other studies with well-characterized model species like Arabidopsis. This article examines the molecular mechanisms governing the adaptability of root system architecture (RSA) to drought stress in plants. It also explores how soil nutrients and microorganisms are regulated in response to these adaptive processes. We first give a general description of how plant hormones control RSA under water-scarce conditions. Additionally, we explore how nutrients, particularly phosphorus and nitrogen, affect the developmental responses of RSA to low water status. Additionally, this article delves into the existing understanding of the interactions between RSA and soil microbial niches under drought. Based on these understandings, our conclusion emphasizes that to achieve a more comprehensive grasp of the mechanisms underlying drought adaptation in plant roots, future research should adopt a holistic network perspective.