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Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology
RESEARCH ARTICLE (Open Access)

The microbiomes on the roots of wheat (Triticum aestivum L.) and rice (Oryza sativa L.) exhibit significant differences in structure between root types and along root axes

Akitomo Kawasaki A F , Paul G. Dennis B , Christian Forstner B , Anil K. H. Raghavendra B F , Alan E. Richardson A , Michelle Watt C , Ulrike Mathesius D , Matthew Gilliham E and Peter R. Ryan https://orcid.org/0000-0002-1376-9543 A G
+ Author Affiliations
- Author Affiliations

A CSIRO Agriculture and Food, PO Box 1700, Canberra, ACT 2601, Australia.

B School of Earth and Environmental Sciences, Faculty of Sciences, The University of Queensland, St Lucia, Qld 4072, Australia.

C School of BioSciences, University of Melbourne, Parkville, Vic. 3010, Australia.

D Division of Plant Sciences, Research School of Biology, Australian National University, Canberra, ACT 2601, Australia.

E ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Glen Osmond, SA 5064, Australia.

F Present address: NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW 2568, Australia.

G Corresponding author. Email: peter.ryan@csiro.au

Functional Plant Biology 48(9) 871-888 https://doi.org/10.1071/FP20351
Submitted: 12 November 2020  Accepted: 22 March 2021   Published: 3 May 2021

Journal Compilation © CSIRO 2021 Open Access CC BY

Abstract

There is increasing interest in understanding how the microbial communities on roots can be manipulated to improve plant productivity. Root systems are not homogeneous organs but are comprised of different root types of various ages and anatomies that perform different functions. Relatively little is known about how this variation influences the distribution and abundance of microorganisms on roots and in the rhizosphere. Such information is important for understanding how root–microbe interactions might affect root function and prevent diseases. This study tested specific hypotheses related to the spatial variation of bacterial and fungal communities on wheat (Triticum aestivum L.) and rice (Oryza sativa L.) roots grown in contrasting soils. We demonstrate that microbial communities differed significantly between soil type, between host species, between root types, and with position along the root axes. The magnitude of variation between different root types and along individual roots was comparable with the variation detected between different plant species. We discuss the general patterns that emerged in this variation and identify bacterial and fungal taxa that were consistently more abundant on specific regions of the root system. We argue that these patterns should be measured more routinely so that localised root–microbe interactions can be better linked with root system design, plant health and performance.

Keywords: rhizosphere, root–microbe interactions, soil microorganisms, Triticum aestivum L., Oryza sativa L., bacterial colonies, fungal colonies, root type, root axes.


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