Suberin in Monocotyledonous Crop Plants: Structure and Function in Response to Abiotic Stresses

Abstract

Apoplastic barriers, formed by Casparian bands and suberin lamellae, represent important means of plant roots to adapt water and nutrient homeostasis to changing environmental conditions. To understand and evaluate the precise physiological role of suberin lamellae in water and nutrient transport characteristics, it is important to understand root anatomy, including main deposition sites and microstructure of suberin. Here we review suberin localization, chemistry, biosynthesis, and differential implementation in dependence of different abiotic stimuli in roots of monocotyledonous crop plants. Furthermore, we add results on the formation of suberized barriers in barley roots under nitrogen and phosphate deficiency, as well as ABA treatments. We conclude that the degree of suberin accumulation is essentially independent of absolute root length, while endodermal plasticity strongly and differentially responds to external environmental stimuli and thus affects plant physiology.

Populus × canescens root suberization in reaction to osmotic and salt stress is limited to the developing younger root tip region

“…However, besides a decrease in root length, often reported in response to many different abiotic stress factors (Grünhofer, Schreiber, & Kreszies, 2021), the root tip swelling phenotype observed in this study (Figure 2) is generally less investigated. The available literature suggests that root tip swelling can be caused by increased starch deposition (Zawaski et al, 2012), which might be linked to stress‐responsive carbohydrate relocation.…”

“…This correlated with the microscopically observed and analytically confirmed enhanced suberization of the root tip (zone A) (Figures 3, 4, S1, and S2). However, based on expectations from comparable studies with different monocotyledonous species (Grünhofer, Schreiber, & Kreszies, 2021), it was surprising how little suberin deposition was increased in P . × canescens overall.…”

“…This correlated with the microscopically observed and analytically confirmed enhanced suberization of the root tip (zone A) (Figures 3, 4, S1, and S2). However, based on expectations from comparable studies with different monocotyledonous species (Grünhofer, Schreiber, & Kreszies, 2021), it was surprising how little suberin deposition was increased in P. Â canescens overall. Especially in the patchy zone B, which was shown to be the most responsive in several cultivars of barley cultivated in the very same laboratory under comparable osmotic stress conditions (Kreszies et al, 2019;Kreszies et al, 2020).…”

“…Root suberization processes might represent a promising target for future genetic manipulation of salinity and drought tolerance, as they were repeatedly identified in stress‐induced reactions in many relatively short‐lived crops (Grünhofer, Schreiber, & Kreszies, 2021; Reinhardt & Rost, 1995; Schreiber et al, 2005). Increased suberization of endo‐ and exodermal cell layers is thought to decrease the plasma membrane surface area available for ion absorption and is speculated to aid in the restriction of uncontrolled water loss (Enstone et al, 2003).…”

Hormonal Crosstalk and Root Suberization for Drought Stress Tolerance in Plants

“…In addition, the ABA-treated wheat observed an improvement of suberin lamellae in root. Arabidopsis accelerated suberin deposition in drought, indicating that drought induces suberin biosynthesis [ 110 ]. Additionally, the suberin limit uncontrolled Na uptake in high-salinity stress in arabidopsis [ 111 ].…”