Do root hairs of barley and maize roots reinforce soil under shear stress?

Burak, E. and Dodd, I.C. and Quinton, J.N. (2021) Do root hairs of barley and maize roots reinforce soil under shear stress? Geoderma, 383. ISSN 0016-7061

[img]
Text (Burak_2020_Do_root_hairs_reinforce_soil_under_shear_stress_1_)
Burak_2020_Do_root_hairs_reinforce_soil_under_shear_stress_1_.pdf - Accepted Version
Restricted to Repository staff only until 5 October 2021.
Available under License Creative Commons Attribution-NonCommercial.

Download (751kB)

Abstract

Roots reinforce soil by acting as soil pins, dissipating shear stresses and anchoring the soil in place. By protruding into the soil and binding to soil particles, root hairs increase root-soil contact and aid root anchorage. However, it is not yet known whether this ability to anchor roots affects the root system's ability to reinforce soil. Using a laboratory box shearing rig, this study explores whether root hairs affect soil shear resistance. The force required to shear soil columns permeated with roots lacking root hairs (barley brb and maize rth3 mutants) are compared to columns permeated with hairy roots (their respective wild types, WT) using unplanted soil columns as controls. Known root traits (e.g. root length density, root surface area density, average diameter, percentage of fine roots, and root tensile strength) were measured to ensure that differences in shear resistance could be attributed to the presence/absence of root hairs. All rooted columns required more force to shear than their respective unplanted columns but the thicker, stronger maize roots were more effective at soil reinforcement than the more numerous but weaker barley roots. After the maximum growth period, root hairs appeared to have a consistent and significant impact on peak shearing force. However, the WT root systems also produced greater root surface area density. As the rate at which peak shearing force increased with increasing root surface area density was similar for roots with and without root hairs, the increased peak shearing force of the WT columns cannot be attributed to resistance supplied by the presence of root hair but rather to a more prolific root system. Therefore, it was concluded that root diameter and root tensile strength most influenced root reinforcement of soil and as such, the relatively minute root hairs had negligible effects compared to their parent roots. © 2020

Item Type:
Journal Article
Journal or Publication Title:
Geoderma
Additional Information:
This is the author’s version of a work that was accepted for publication in Geoderma. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Geoderma, 383, 2020 DOI: 10.1016/j.geoderma.2020.114740
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/1100/1111
Subjects:
ID Code:
149151
Deposited By:
Deposited On:
17 Nov 2020 14:50
Refereed?:
Yes
Published?:
Published
Last Modified:
23 Nov 2020 13:56