Buffalo, New York, USA
State University of New York
Williamsville East HS
London, Ontario, Canada
University of Western Ontario
Taipei, Taiwan, Republic of China
National Taiwan University
3D visualization of stem by MRI technology --Cheng, P-c, Chen, J-H, Lin, C-P, Sun, C-K, Walden, DB, Cheng, WY Recent development in confocal and multi-photon fluorescence microscopy allows 3D imaging of plant tissue in high resolution. However, other than physical sectioning, macroscopical study of plant organs in 3D remains a difficult task. Among various available technologies for macroscopical imaging (e.g., X-ray macro-tomography, optical coherent tomography and MRI), MRI is an ideal choice for its contrasting modality in volumetric imaging of soft tissues. In this study, a 3T Biospect MRI system (Brucker, Germany) equipped with a 6cm inner diameter micro-quadrature coil for RF transmission and reception of MRI signals was used. Spin echo based RARE sequence was used to obtain T2 weighted images with TR/TE = 3160.5/58.5ms and field-of-view of 1.67cm x 1.67cm (256 x 256 pixels) at a slice thickness of 0.8mm. This corresponds to a pixel size of 65 x 65 x 800mm. Data were obtained over 0.5 hour with number-of-excitations (nex) set at 16.

Figures (1)-(12) (following page) show a series of MRI cross-sections through a node (the node below the main ear insertion) from field-grown maize stem (Odyssey sweet corn). The stem was fixed in 1:3 EtOH/acetic acid, and washed thoroughly in water prior to imaging. Air bubbles trapped in the leaf sheath were removed by vacuuming to avoid imaging artifact due to low magnetic susceptibility of air. Note the branching pattern of vascular bundles in the node. The image set shown in this article is suitable for computer 3D reconstruction and visualization. Tracing and reconstruction of vascular bundles in the node region is possible.

This project was supported by the National Science Council, Republic of China under grant number NSC-88-2811-B-001-0023 (PCC), NSC-89-2811-E-002-0058 (PCC), NSC-89-2215-E-002-064 (CKS). The Biospec MRI facility is a national user facility funded by the National Science Council, Republic of China and operated by the Precision Instrument Center, National Taiwan University.

Please Note: Notes submitted to the Maize Genetics Cooperation Newsletter may be cited only with consent of the authors.

Return to the MNL 75 On-Line Index
Return to the Maize Newsletter Index
Return to the Maize Genome Database Page