Effect of mechanical damage and wound healing on the viscoelastic properties of stems of flax cultivars (Linum usitatissimum L. cv. Eden and cv. Drakkar)

PLoS One. 2017 Oct 5;12(10):e0185958. doi: 10.1371/journal.pone.0185958. eCollection 2017.

Abstract

As plant fibres are increasingly used in technical textiles and their composites, underlying principles of wound healing in living plant fibres are relevant to product quality, and provide inspiration for biomimetic healing in synthetic materials. In this work, two Linum usitatissimum cultivars differing in their stem mechanical properties, cv. Eden (stems resistant to lodging) and cv. Drakkar (with more flexible stems), were grown without wound or with stems previously wounded with a cut parallel or transversal to the stem. To investigate wound healing efficiency, growth traits, stem biomechanics with Dynamic Mechanical Analysis and anatomy were analysed after 25-day recovery. Longitudinal incisions formed open wounds while transversal incisions generated stem growth restoring the whole cross-section but not the original stem organisation. In the case of transversal wound healing, all the bast fibre bundles in the perturbed area became lignified and pulled apart by parenchyma cells growth. Both Linum cultivars showed a healing efficiency from 79% to 95% with higher scores for transversal healing. Morphological and anatomical modifications of Linum were related to mechanical properties and healing ability. Alongside with an increased understanding of wound healing in plants, our results highlight their possible impact on textile quality and fibre yield.

MeSH terms

  • Elasticity
  • Flax / physiology*
  • Models, Theoretical
  • Plant Stems / physiology*
  • Stress, Physiological*
  • Viscosity
  • Wound Healing*

Grants and funding

Funding from the European Union Seventh Framework Program (FP7/ 2007-2013) under grant agreement no. 290308 (Marie Curie ITN SHeMat ‘Self-Healing Materials: from Concepts to Market’) is gratefully acknowledged. We thank "Terre de Lin" for providing Linum usitatissimum seeds. We thank Heidi Petarus and her team of the Botanic Garden of the University of Freiburg (Germany) for assistance in plant growing. We thank Sabine Diener, Susanne Röske and Nardo Streit (Institute for Forest Botany, University of Freiburg, Germany) for technical assistance in the anatomical sample preparation. The article processing charge was funded by the German Research Foundation (DFG) and the University of Freiburg in the funding programme Open Access Publishing.