A qualitative analysis of the bud ontogeny of Dracaena marginata using high-resolution magnetic resonance imaging

Abstract

The development of the branch-stem-attachment of Dracaena marginata was analyzed to clarify how a load-adapted arrangement of mechanically relevant tissues, i.e. the vascular bundles with fiber caps, is established during ontogeny. For this purpose, 3D images of four intact and developing buds of D. marginata were repetitively acquired in vivo within the time span of 180 days using high-resolution magnetic resonance imaging, as this method allows for non-invasive and non-destructive image acquisition. This methodical approach enabled the classification of distinct ontogenetic stages revealing the complex ontogeny of the branch-stem-attachment in D. marginata and the establishment of a load-adapted tissue arrangement within the junction between branch and main stem. This further allows for a first biomimetic abstraction and the transfer into a technical implementation of the form-structure-function principles found in branchings in D. marginata.

A Mobile NMR Sensor and Relaxometric Method to Non-destructively Monitor Water and Dry Matter Content in Plants

“…It is best known for its applications in Nuclear Magnetic Resonance Imaging (MRI, also abbreviated to MR imaging, or NMRi) in human medicine, but also has found many applications in plant science. Recent applications of MRI include imaging plant anatomy, for example of tree stems affected by disease (Kuroda et al, 2006), bud ontogeny (Hesse et al, 2018), imaging of fruits and crops (Glidewell, 2006), water content and cavitation events in stems (Holbrook et al, 2001;Choat et al, 2010;De Schepper et al, 2012;Hochberg et al, 2016;Van de Wal et al, 2017;Meixner et al, 2020), structure and function of roots in soils (Jahnke et al, 2009;Kaufmann et al, 2009;van Dusschoten et al, 2016), imaging xylem-and phloem sap flow in stems and petioles (Scheenen et al, 2000(Scheenen et al, , 2007Windt et al, 2006Windt et al, , 2009, or micro imaging of seeds (Sreenivasulu et al, 2010;Munz et al, 2017). For comprehensive overviews we refer to Van As (2007) and Borisjuk et al (2012).…”

A small‐scale MRI scanner and complementary imaging method to visualize and quantify xylem embolism formation

“…MRI is thus well suited for continuous or long‐term measurements. The technology has been used to image structure and anatomy (Robinson et al , ; Metzner et al , ; Hesse et al , ), plant water content (Schepper et al , ), and to measure phloem and xylem sap flow (Köckenberger et al , ; Scheenen et al , ; Windt et al , ). For detailed reviews and more examples see van As et al () and Borisjuk et al ().…”

Branching morphology and biomechanics of ivy (Hedera helix) stem‐branch attachments

“…In D. reflexa and F. insignis (as tested by Masselter et al, 2011), fracture toughness values in the stem-branch attachments are in a similar range (with mean values of 10.53 and 9.32 kJ/m 2 , respectively) as the fracture toughness of "old" (DoF2) axes of H. helix, with a median value of 11.60 kJ/m 2 . This similarity indicates that self-supporting axes of relatively thin-stemmed, but otherwise very different plants (D. reflexa and F. insignis are monocotyledons with a fundamentally different stem anatomy from H. helix) (Haushahn et al, 2014;Hesse et al, 2016Hesse et al, , 2018Masselter et al, 2016) and a different ontogeny (D. reflexa does not produce climbing phases), have similar values of fracture toughness (a finding that also holds for Schefflera arboricola, data not shown). Therefore, it might be deduced that these comparable values result from similar mechanical constraints in self-supporting branched plants.…”

“…Complementary techniques can allow a fuller understanding of the functional morphology and biomechanics of the Araliaceae family, for example, by testing the anatomy (inner structure) of H. helix ramifications under load via methods such as magnetic resonance imaging, thus allowing for a non-invasive loading of plant specimens in vivo, as well as a fundamental exploration of branch formation (Hesse et al, 2016(Hesse et al, , 2018. In conjunction, such analyses can provide a foundation for the development of biomimetic node structures for implementation in constructional engineering and architecture, e.g., by mimicking the "finger-like" attachment structures between branch and stem in the Araliaceae (Born et al, 2016;Bunk et al, 2017b).…”