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3D imaging and mechanical modeling of helical buckling in Medicago truncatula plant roots.

ABSTRACT: We study the primary root growth of wild-type Medicago truncatula plants in heterogeneous environments using 3D time-lapse imaging. The growth medium is a transparent hydrogel consisting of a stiff lower layer and a compliant upper layer. We find that the roots deform into a helical shape just above the gel layer interface before penetrating into the lower layer. This geometry is interpreted as a combination of growth-induced mechanical buckling modulated by the growth medium and a simultaneous twisting near the root tip. We study the helical morphology as the modulus of the upper gel layer is varied and demonstrate that the size of the deformation varies with gel stiffness as expected by a mathematical model based on the theory of buckled rods. Moreover, we show that plant-to-plant variations can be accounted for by biomechanically plausible values of the model parameters.

SUBMITTER: Silverberg JL

PROVIDER: S-EPMC3479456 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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3D imaging and mechanical modeling of helical buckling in Medicago truncatula plant roots.

Silverberg Jesse L JL Noar Roslyn D RD Packer Michael S MS Harrison Maria J MJ Henley Christopher L CL Cohen Itai I Gerbode Sharon J SJ

Proceedings of the National Academy of Sciences of the United States of America 20120924 42

We study the primary root growth of wild-type Medicago truncatula plants in heterogeneous environments using 3D time-lapse imaging. The growth medium is a transparent hydrogel consisting of a stiff lower layer and a compliant upper layer. We find that the roots deform into a helical shape just above the gel layer interface before penetrating into the lower layer. This geometry is interpreted as a combination of growth-induced mechanical buckling modulated by the growth medium and a simultaneous ...[more]

PMID: 23010923

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Dataset Information

3D imaging and mechanical modeling of helical buckling in Medicago truncatula plant roots.

Publications

3D imaging and mechanical modeling of helical buckling in Medicago truncatula plant roots.

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