Multiple origins of dichotomous and lateral branching during root evolution

ABSTRACT Roots of extant vascular plants proliferate through lateral branching (euphyllophytes) or dichotomy (lycophytes)1,2,3,4. The origin of these distinct modes of branching was key for

plant evolution because they enabled the development of structurally and functionally different root systems that supported a diversity of shoot systems3,4,5,6. It has been unclear when

lateral branching originated and how many times it evolved4,7,8. Here, we report that many euphyllophytes that were extant during the Devonian and Carboniferous periods developed dichotomous

roots. Our data indicate that dichotomous root branching evolved in both lycophytes and euphyllophytes. Lateral roots then evolved at different times in three major lineages of extant

euphyllophytes—the lignophytes, ferns and horsetails. The multiple origins of dichotomous and lateral root branching are extreme cases of convergent evolution that occurred during the

Devonian and Carboniferous periods when the land-plant flora underwent a radiation in morphological diversity. Access through your institution Buy or subscribe This is a preview of

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ACCESS OPTIONS: * Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS DIVERGENT EVOLUTIONARY TRAJECTORIES OF

BRYOPHYTES AND TRACHEOPHYTES FROM A COMPLEX COMMON ANCESTOR OF LAND PLANTS Article Open access 29 September 2022 MYCORRHIZAS DRIVE THE EVOLUTION OF PLANT ADAPTATION TO DROUGHT Article Open

access 30 March 2023 GENE EXPRESSION DATA SUPPORT THE HYPOTHESIS THAT _ISOETES_ ROOTLETS ARE TRUE ROOTS AND NOT MODIFIED LEAVES Article Open access 09 December 2020 DATA AVAILABILITY The

paratype ULG 2057a and ULG 2057b of _L. goense_ is housed in the collections of the University of Liège, Belgium. All other data supporting the findings of this study are included in the

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Pennsylvania, USA. _Int. J. Coal Geol._ 83, 91–102 (2010). CAS  Google Scholar  Download references ACKNOWLEDGEMENTS A.J.H. thanks C. Prestianni for help and hospitality while examining the

collections of The University of Liège, as well as L. Ji and S. Snigirevsky for assistance with translation. A.J.H. was funded by the George Grosvenor Freeman Fellowship by Examination in

Sciences, Magdalen College (Oxford); L.D. by a European Research Council Advanced Grant (EVO500, contract 250284), European Commission Framework 7 Initial Training Network (PLANTORIGINS,

project identifier 238640) and European Research Council Grant (De NOVO-P, contract 787613); and C.M.B. by NERC grant NE/J007897/1. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department

of Plant Sciences, University of Oxford, Oxford, UK Alexander J. Hetherington & Liam Dolan * School of Earth and Ocean Sciences, Cardiff University, Cardiff, UK Christopher M. Berry

Authors * Alexander J. Hetherington View author publications You can also search for this author inPubMed Google Scholar * Christopher M. Berry View author publications You can also search

for this author inPubMed Google Scholar * Liam Dolan View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS A.J.H. designed the project with

advice from L.D. and C.M.B.; A.J.H. performed the analyses with assistance from C.M.B.; and A.J.H. and L.D. wrote the paper with comments from C.M.B. CORRESPONDING AUTHOR Correspondence to

Alexander J. Hetherington. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. ADDITIONAL INFORMATION PEER REVIEW INFORMATION _Nature Plants_ thanks Deming

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AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Hetherington, A.J., Berry, C.M. & Dolan, L. Multiple origins of dichotomous and lateral branching during

root evolution. _Nat. Plants_ 6, 454–459 (2020). https://doi.org/10.1038/s41477-020-0646-y Download citation * Received: 13 November 2019 * Accepted: 24 March 2020 * Published: 04 May 2020 *

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