Differing nodal structure in oat and wheat

Authors: Heuschele, Deborah; VANHEEL, BONITA - University Of Minnesota; HE, YING - University Of Minnesota; FOK, ALEXANDER - University Of Minnesota

Submitted to: Discover Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2025
Publication Date: 5/30/2025
Citation: Heuschele, D.J., Vanheel, B., He, Y., Fok, A. 2025. Differing nodal structure in oat and wheat. Discover Agriculture. 3. Article 85. https://doi.org/10.1007/s44279-025-00242-3.
DOI: https://doi.org/10.1007/s44279-025-00242-3

Interpretive Summary: Obtaining 3D images of internal plant structures without destroying the plant is invaluable, making micro-CT a good imaging tool. Unfortunately, plant tissue is lower in density compared to other biological materials such as teeth or bone. In order to create quality 3D images of plants, we developed a method to fix and contrast stems of oat and wheat at high resolution. This method results in time savings while improving the quality and details of the images. This surpasses older methods using light microscopy for understanding stem structures for improving plant productivity and environmental resilience.

Technical Abstract: Background Micro-CT (X-ray computed tomographic) allows 3D visualization of an entire structure, both internally and externally. The different materials are identified based on the differences in their ability to attenuate X-ray, with the differences being converted into a range of grey values. Low-density plant tissues with limited differences in grey values create a challenge in differentiating the cellular structures. In addition, internal movements due to autolysis, degradation, and shrinkage during dehydration of the tissues during scanning give rise to blurry images. Results In this study, oats and wheat were scanned using micro-CT to optimize the use of micro-CT in low-density plants. With the assistances of chemical fixing, phosphotunstate and a chemical drying agent, we were able to visualize microstructures of cereal stems. These preparation steps allow us to create 3-D micrographs of low-density stem nodes suggesting key structural differences that are correlated with lodging resistance. Conclusion Micro-CT is a valuable tool to create 3-D structural images of low-density material. Multiple steps to prepare the samples to stop autolysis, increase the contrast during scanning and eliminate internal movement are described in this paper. This process allowed for visualization of stem nodal region suggesting morphology related to lodging resistance.