Abstract
Here we describe an in vivo dye-tracking method for measuring phloem transport velocity in seedlings, leaves and petioles and potentially other translucent plant tissues. The method requires measurement of the fluorescent signal of a phloem-mobile fluorescent dye using sensitive photo-sensors placed external to the plant. Following dye application, velocity is determined using laser fluorescence bleaching and measuring the time it takes for the bleach front to reach a light sensor. This method can be used to measure phloem transport velocity on intact plants with minimal disturbance and has a potential to be used under a variety of growth conditions and in the field. Because there are large differences among species in their anatomy, this method should be optimized to individual plants and tissue types.
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Acknowledgments
This work was partially supported by the National Science Foundation Integrative Organismal Systems 1656318 (JAS).
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Savage, J.A., Zwieniecki, M.A. (2019). Measuring Phloem Transport Velocity on a Tissue Level Using a Phloem-Mobile Dye. In: Liesche, J. (eds) Phloem. Methods in Molecular Biology, vol 2014. Humana, New York, NY. https://doi.org/10.1007/978-1-4939-9562-2_17
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DOI: https://doi.org/10.1007/978-1-4939-9562-2_17
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