Optical coherence tomography for visualization of plant tissues

First experimental results on optical coherence tomography (OCT) imaging of internal structure of plant tissues and in situ OCT monitoring of plant tissue regeneration at different water supply are reported. The OCT images are a map of backscattering coefficient 200x200 pixels, 1.5 mm along plant surface and up to 2 mm in depth (by analogy with ultrasound B-scan). Experiments for evaluating OCT capabilities were performed on Tradescantia blossfeldiana Mild. Using OCT device, in vivo images of plant tissues were acquired with a spatial resolution of 15 mum. These OCT images correlate with standard microscopy data from the same tissue regions. Since incident light power at a wavelength of 1.3 gin is as low as 0.5 mW, two-dimensional OCT images can be obtained directly on an intact plant not damaging it. Acquisition time for a 2D image is 1-3 s. OCT enables effective monitoring of fast reactions in plants at different water supply.