Iohexol was successfully transported through the xylem and marked conductive vessels on HRCT scans. The results obtained in vivo using iohexol were generally comparable to those obtained in stained cut segments, although iohexol allowed identification of a greater number of smaller conduits in some samples7.
It was possible to distinguish between gas-filled conduits, conductive conduits (containing iohexol tracer) and non-conductive conduits (no iohexol tracer present). The differentiation of conduit type showed only minimal differences between the visualisation in intact plants and the evaluation of excised segments.
Most importantly, both vessels and vasicentric tracheids were filled with iohexol in the chestnut plant, providing a new tool to study the functions of these different cell types7.
This latest research suggests that iohexol represents an important tracer for enabling the identification of conductive vessels in intact plants and may greatly improve the utility of HRCT as a tool in the study of plant hydraulic function.
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