Anatomy and Biomechanics of Peltate Begonia Leaves—Comparative Case Studies

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Annabell Rjosk - , Chair of Botany, TUD Dresden University of Technology (Author)
  • Christoph Neinhuis - , Chair of Botany, TUD Dresden University of Technology (Author)
  • Thea Lautenschläger - , Chair of Botany, TUD Dresden University of Technology (Author)

Abstract

Plants are exposed to various external stresses influencing physiology, anatomy, and morphology. Shape, geometry, and size of shoots and leaves are particularly affected. Among the latter, peltate leaves are not very common and so far, only few studies focused on their properties. In this case study, four Begonia species with different leaf shapes and petiole attachment points were analyzed regarding their leaf morphology, anatomy, and biomechanical properties. One to two plants per species were examined. In all four species, the petiole showed differently sized vascular bundles arranged in a peripheral ring and subepidermal collenchyma. These anatomical characteristics, low leaf dry mass, and low amount of lignified tissue in the petiole point toward turgor pressure as crucial for leaf stability. The petiole-lamina transition zone shows a different organization in leaves with a more central (peltate) and lateral petiole insertion. While in non-peltate leaves simple fiber branching is present, peltate leaves show a more complex reticulate fiber arrangement. Tensile and bending tests revealed similar structural Young’s moduli in all species for intercostal areas and venation, but differences in the petiole. The analysis of the leaves highlights the properties of petiole and the petiole-lamina transition zone that are needed to resist external stresses.

Details

Original languageEnglish
Article number3297
JournalPlants
Volume11
Issue number23
Publication statusPublished - Dec 2022
Peer-reviewedYes

Keywords

Keywords

  • anatomy, Begonia, biomechanics, peltate leaves, petiole-lamina transition zone