Growing Out of Stress: The Role of Cell- and Organ-Scale Growth Control in Plant Water-Stress Responses

Abstract

Water is the most limiting resource on land for plant growth, and its uptake by plants is affected by many abiotic stresses, such as salinity, cold, heat, and drought. While much research has focused on exploring the molecular mechanisms underlying the cellular signaling events governing water-stress responses, it is also important to consider the role organismal structure plays as a context for such responses. The regulation of growth in plants occurs at two spatial scales: the cell and the organ. In this review, we focus on how the regulation of growth at these different spatial scales enables plants to acclimate to water-deficit stress. The cell wall is discussed with respect to how the physical properties of this structure affect water loss and how regulatory mechanisms that affect wall extensibility maintain growth under water deficit. At a higher spatial scale, the architecture of the root system represents a highly dynamic physical network that facilitates access of the plant to a heterogeneous distribution of water in soil. We discuss the role differential growth plays in shaping the structure of this system and the physiological implications of such changes.

The battle of two ions: Ca2+ signalling against Na+ stress

“…Ethylene appears to be involved in establishing root growth inhibition under saline conditions (Feng et al . ). Ethylene inhibits growth at least in part via DELLA‐dependent mechanisms (Harberd et al .…”

Functional implications of root cortical senescence for soil resource capture

“…3). Reduced radial hydraulic conductivity may be advantageous under water limited conditions by conserving soil water throughout the growth season, a strategy known as Bwater banking^ (Feng et al 2016). Reduced metaxylem vessel diameter conserves soil water throughout the growth season (Richards and Passioura 1989).…”

Brassinosteroid Mediated Cell Wall Remodeling in Grasses under Abiotic Stress

“…Among abiotic stresses, water-deficiency through drought, osmotic stress and salinity are the most challenging for crop growth and food production (Tenhaken, 2015; Feng et al, 2016). The water potential of the plant cell is in accordance with that of the environment surrounding the cell (Bray, 2007).…”

“…They subsequently translate the physical changes in the cell surface to cellular signals (such as Ca 2+ influx), which further trigger corresponding cascades of plant defense responses for stress management (Hamann and Denness, 2011; Feng et al, 2016). These responses are better understood in yeast than in plants (Hamann and Denness, 2011).…”