| Abstract Detail
Recent Topics Posters Bogart, Sarah J. [1], Cholewa, Ewa [2], Spiers, Graeme [3], Elliot, Thomas R. [4]. X-ray µCT as a developing tool for 3D tissue realization within an herbaceous wetland plant, Eriophorum vaginatum. In nutrient limited environments such as arctic tundra and ombrogenous bogs, the perennial survival of sedges is dependent upon efficient nutrient recycling and storage within their storage organs (corms and rhizomes). One such species, Eriophorum vaginatum, contains anatomical features atypical to monocotyledonous plants, i.e. red-orange sclereid clusters adaxial to vascular bundles and a horizontal vascular ring, which are suspected to facilitate nutrient recycling within the corm. This study focuses on the technical and methodological optimization of X-ray µCT for non-destructive investigation of these poorly understood tissues of E. vaginatum. Various scanning parameters (voxel resolution, X-ray energy and current) were compared for their ability to differentiate tissues located in the corm of E. vaginatum. Optimal resolution for X-ray µCT scans was observed at 10µm (vs. scans at 50µm and 20µm) however, differentiation of vascular bundles from surrounding tissues was limited. Subsequent lower energy (45kVp) scans to optimize soft tissue contrast, combined with variations in current (50, 100, and 200µA), resulted in an increase in image noise such that images were unusable without image processing. A homomorphic image filter (Gaussian blur radius of ~2 pixels), applied to the 16-bit images, dramatically improved the differentiation of corm tissues. Using knowledge of E. vaginatum anatomy gained from hand-sections, preliminary 3D maps (isosurfaces) of corm tissues were created by segmenting tissues from images using the Otsu79 thresholding-function within MicroView 2.1.2. Despite visual optimization efforts, these maps contained misclassification errors of some voxels, which are likely due to similarities in the radiodensity of multiple tissues. Hence, the quantitative accuracy of these datasets must be investigated once a more appropriate segmentation method is located. Our results are a proof of concept that herbaceous-plant tissues can be examined using X-ray µCT but that further research is required to improve the accuracy of tissue segmentation. Log in to add this item to your schedule
1 - Laurentian University, Department of Biology, 935 Ramsey Lake Road, Sudbury, ON, P3E 2C6, Canada 2 - Nipissing University, Department of Biology, 100 College Drive, North Bay, ON, P1B 8L7, Canada 3 - Laurentian University, Centre for Environmental Monitoring, MIRARCO, 935 Ramsey Lake Road, Sudbury, ON, P3E 2C6, Canada 4 - University of Guelph, Department of Land Resource Science, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
Keywords: Eriophorum vaginatum X-ray computed tomography corm tissue morphology herbaceous plant.
Presentation Type: Recent Topics Poster Session: P Location: Ball Room & Party Room/SUB Date: Monday, July 28th, 2008 Time: 12:30 PM Number: PRT002 Abstract ID:1108 |