2019 ASHS Annual Conference

Understanding root system architecture, and the biotic and abiotic factors that influence its development, is complicated by our current inability to directly observe these processes with genuine fidelity. In an effort to approach biologically relevant non-destructive in situ imaging of roots and root development, we have been using X-ray tomography (XRT) to look into the rhizosphere over a range of biological scales. In particular we’re interested in the influence of root-microbe interaction on root system architecture in a variety of economically important crop plants over multiple environmental conditions. Our large-scale, high resolution industrial XRT instrument can image complete root systems in a variety of growth media down to 35µm voxel resolution. In addition, we’re using an X-ray microscope (XRM) to examine root nodule formation by beneficial nitrogen-fixing bacteria, and root colonization by mycorrhizal fungi, both in vivo and with fixed and contrast-enhanced samples. These imaging technologies yield three-dimensional (3D) scan volumes that are rich in data, once the critical biological features are computationally segmented from the scan volumes, currently the greatest challenge in any tomographic imaging strategy. The combination of X-ray imaging and advanced computational analyses is being used to observe, identify, and measure rhizosphere biology in ways not previously practical or possible. In addition, we are exploring the use of Virtual Reality-Augmented Reality (VRAR) as innovative tools for both visualization and segmentation of 3D imaging data.

This work is supported by collaborative agreements with Valent BioSciences, Sumitomo Chemical Company, and the National Science Foundation projects EPSCoR IIA-1355406, PGRP IOS-1638507, and DBI-1759796.