Micro-CT for the Study of Plant Root Function in a Cactus

Root biology research has been ongoing for more than a century but has rarely been the focus of research by mainstream biologists. Recently, however, micro-CT and other newer technologies have led to numerous insights and stimulated a new generation of root biologists. Root systems play a critical role in our environment by preventing erosion and are key to efficient nutrient uptake in plants. In most plants the root system is below ground, and less familiar than flowers, stems, and leaves, but they are equally important to the plants. Root function studies could help agricultural biologists breed plants with more efficient nutrient absorption and reduce the need for fertilizers.

 In cactus plants, as in our example micro-CT image this month, the roots function as a hydraulic safety valve. They conduct the uptake of available water quickly and prevent water loss under drought conditions. Further studies of these critical systems can help scientists better understand evolutionary adaptations to extreme drought. Micro-CT allows researchers to non-destructively study the morphological and functional features of cactus root systems from a hydrodynamic viewpoint.

For our study this month, we utilized our high speed SkyScan 1275 desktop scanner to non-destructively visualize a living cactus.

Micro-CT Scan of a Cactus

Utilizing the reconstructed X-ray attenuation data, two-dimensional views through the cactus were generated (Figure 1). While many biological samples are inherently non-planar, plants often contain inherent degrees of symmetry. Additionally, the ability of DataViewer to reorient samples interactively on the fly when working with reconstructed datasets allows users to further refine the planar views.

For a broader qualitative view of the cactus than is available in the planar two-dimensional views, the reconstructed images also provide a full three-dimensional rendering of the cactus using CTVox. This three-dimensional rendering can be positioned and sliced as needed to provide greater dimensional context to the internal features (Figure 2). In this case, we can digitally dissect the sample to gain visual information on the root structures and their pathway into the plant, which can be used for further identification and studies.

Conclusion

Micro-CT is being rapidly adopted in fields ranging from structural biology and material science to geology, odontology, and many other manufacturing industries. We hope you found this Image of the Month informative. If you have an Image of the Month sample that you would like us to scan, please contact us by calling Seth Hogg at 610-366-7103 or e-mailing seth.hogg@microphotonics.com

Scan Specifications

This scan was completed on our large volume SkyScan 1275 micro-CT system at the Micro Photonics Imaging Laboratory in Allentown, PA. Reconstructions were completed using NRecon and visualization of 2D and 3D results were completed using DataViewer and CTVox.