Root Development and Stress Tolerance in rice: The Key to Improving Stress Tolerance without Yield Penalties

Abstract

Roots anchor plants and take up water and nutrients from the soil; therefore, root development strongly affects plant growth and productivity. Moreover, increasing evidence indicates that root development is deeply involved in plant tolerance to abiotic stresses such as drought and salinity. These findings suggest that modulating root growth and development provides a potentially useful approach to improve plant abiotic stress tolerance. Such targeted approaches may avoid the yield penalties that result from growth–defense trade-offs produced by global induction of defenses against abiotic stresses. This review summarizes the developmental mechanisms underlying root development and discusses recent studies about modulation of root growth and stress tolerance in rice.

Salt Stress Promotes Abscisic Acid Accumulation to Affect Cell Proliferation and Expansion of Primary Roots in Rice

“…As a belowground organ, roots anchor plants and take up water and nutrients from the soil. Root development therefore strongly affects plant growth and productivity [ 1 ]. Rice is a staple crop for half of the world’s population and improving the root system of rice is conducive to increasing the yield of crops and their ability to cope with adverse environments [ 1 , 2 , 3 ].…”

“…Root development therefore strongly affects plant growth and productivity [ 1 ]. Rice is a staple crop for half of the world’s population and improving the root system of rice is conducive to increasing the yield of crops and their ability to cope with adverse environments [ 1 , 2 , 3 ]. Salinity stress is one of the major constraints on plant growth, affecting rice productivity worldwide, and roots are the primary target site for perception of salt stress signals which could act as an early warning system for the plant [ 4 , 5 ].…”

Root Involvement in Plant Responses to Adverse Environmental Conditions

“…Although most studies on abiotic stress resistance mechanisms focus on aerial organs, mainly because of the difficulty to study roots in their natural environment, it has been pointed out that aboveground and belowground organs have distinct responses (reviewed in [2,3]), and physiological and molecular mechanisms leading to stress tolerance can be complementary but not identical among tissues and organs [4]. Taking this into consideration, novel strategies for the development of crops with improved tolerance to abiotic stress conditions, based on targeting specific tissues or organs (instead of the entire plant) are emerging (reviewed in [5]). Root is a key organ since it is involved in the uptake of water and nutrients, anchors the plant to the substrate and it is crucial for plant performance and crop productivity [6].…”

Pinpointing genomic regions associated with root system architecture in rice through an integrative meta-analysis approach

“…The OsARD4 overexpression contributed to the root growth by increasing the rates of radical emergence, elongation of primary roots and initiation of lateral/crown roots and raising the root biomass compared to that of nontransgenic plants (Ramanathan et al 2018). Plant root lignification play an effective role in tolerance to abiotic stresses such as drought (Seo et al 2020). As an important enzyme of the lignin biosynthetic pathway, Cinnamoyl-CoA reductase (CCR) controls the quality and quantity of lignin (Jones et al 2001).…”