Ice propagation in the wood visualized by IDTA (Neuner)

Ice propagation in the wood visualized by IDTA

Introduction
Ice propagation in the wood visualized by IDTA Xylem parenchyma cells of many trees from cold regions exhibit deep supercooling while cortical and cambial tissues survive by extracellular equilibrium freezing. Deep supercooling is a frost survival mechanism effective down to a temperature of about -40°C which critically limits the distribution of a species.
Deep supercooling is detectable by thermocouple DTA but the freezing processes can only be localized in combination with complex viability assays. Differential infrared thermography (IDTA) was developed in research group of G. Neuner and allows the tracking of ice nucleation and propagation. We aimed to apply IDTA to the surface of cross and longitudinal sections of woody stem segments to check whether it is possible to visualize stem freezing patterns.

Research Questions

Visualization of the break-down of supercooling of xylem parenchyma cells
Two dimensional visualization of patterns of intracellular freezing of xylem parenchyma cells
two dimensional ice propagation patterns in different tissues of woody stems
initial site of ice nucleation in woody stems (bark or xylem tissue)

Publications
NEUNER, G., XU, B., HACKER, J. Velocity and pattern of ice propagation and deep supercooling in woody stems of Castanea sativa, Morus nigra and Quercus robur measured by IDTA. Tree Physiology, 30, 1037-1045, DOI 10.1093/treephys/tqp059 (2010).

Funding
2007-2008 EURASIA PACIFIC UNINET project (461-20/BAMO/2006) (PI: Gilbert NEUNER)

Personnel involved
Bingcheng XU
Jürgen HACKER
Gilbert NEUNER