Imaging microstructure of the barley rhizosphere: particle packing and root hair influences

DOI: 10.1111/nph.15516

Authors: Nicolai Koebernick (University of Southampton) , Keith R. Daly (University of Southampton) , Samuel D. Keyes (University of Southampton) , Anthony G. Bengough (The James Hutton Institute; University of Dundee) , Lawrie K. Brown (The James Hutton Institute) , Laura J. Cooper (University of Southampton; University of Warwick) , Timothy S. George (The James Hutton Institute) , Paul D. Hallett (University of Aberdeen) , Muhammad Naveed (University of Aberdeen; University of West London) , Annette Raffan (University of Aberdeen) , Tiina Roose (University of Southampton)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: New Phytologist

State: Published (Approved)
Published: October 2018
Diamond Proposal Number(s): 12525

Abstract: Soil adjacent to roots has distinct structural and physical properties from bulk soil, affecting water and solute acquisition by plants. Detailed knowledge on how root activity and traits such as root hairs affect the 3D pore structure at a fine scale is scarce and often contradictory. Roots of hairless barley (Hordeum vulgare L. cv ‘Optic’) mutant (NRH) and its wildtype (WT) parent were grown in tubes of sieved (<250 μm) sandy loam soil under two different water regimes. The tubes were scanned with synchrotron based X‐ray CT to visualise pore structure at the soil‐root interface. Pore volume fraction and pore size distribution were analysed versus distance within 1 mm of the root surface. Less dense packing packing of particles at the root‐surface was hypothesised to cause the observed increased pore volume fraction immediately next to the epidermis. The pore size distribution was narrower due to a decreased fraction of larger pores. There were no statistically significant differences in pore structure between genotypes or moisture conditions. A model is proposed that describes the variation in porosity near roots taking into account soil compaction and the surface effect at the root surface.

Journal Keywords: Root hairs; rhizosphere; Hordeum vulgare; noninvasive imaging; synchrotron; soil structure; particle packing

Subject Areas: Biology and Bio-materials


Instruments: I13-1-Coherence

Added On: 24/10/2018 10:27

Discipline Tags:

Plant science Agriculture & Fisheries Life Sciences & Biotech

Technical Tags:

Imaging Tomography