Phenotyping Plant Cellular and Tissue Level Responses to Cold with Synchrotron-Based Fourier-Transform Infrared Spectroscopy and X-Ray Computed Tomography.

Despite the extensive use of synchrotron radiation in material and biomedical sciences, it has only recently been utilized to expand our understanding of plant responses to environmental stress. Recent advances have led to the development of phenotyping platforms to identify chemical and morphological differences in breeding plant material. While these methodologies are applicable for and tested with a variety of abiotic and biotic stresses, they are particularly useful as a first step to identify cold-induced chemical and morphological changes in plants. Here, we describe two methods to determine cold acclimation-induced changes at the cellular and tissue levels. First, we illustrate how to quantify and visualize changes in tissue chemistry using Fourier-transform infrared spectroscopy. Second, we describe how to nondestructively prepare, analyze, and interpret X-ray phase contrast images and render this data as two- or three-dimensional models. While these techniques utilize synchrotron radiation, the methodology and standard practices are applicable for handheld and laboratory bench-top equipment operating with conventional light sources.