Ice propagation in plants during radiative frost

Ice nucleation and propagation and resultant functional disturbances are studied at the cellular level using two new innovative technologies under field conditions. Freezing survival mechanisms are analysed in alpine plants as they have a large potential to act as model organisms for plant freezing tolerance in a metabolically active state. Freezing stress is an important environmental factor that limits the distribution of wild plants and crop species and can cause severe yield losses in agriculture. Therefore, understanding of freezing and how it damages plants is of extensive practical importance. Although current strategies for achieving understanding of freezing tolerance often focus on molecular analysis of cold acclimation, it is equally important to understand the freezing process itself. Knowledge of the exact mechanisms how plant tissues freeze is essential for developing rational strategies e.g. for conferring freeze-tolerance in species that have no tolerance of freezing. For studies of the freezing process in plants a recently invented, powerful technology, i.e. infrared thermography (IRT), offers the new possibility to determine frost tolerance mechanisms, i.e. supercooling or tolerance of extracellular ice, at the plant tissue level. IRT gives a real time image of the plant surface temperature, thus revealing the location at which ice first forms and showing the route and rate of initial growth of ice through the plant. An equally new method is the chlorophyll fluoroscence imaging technique , that allows in combination with IRT measurements to monitor the spread of intrinsic ice and concomitantly potential freezing induced functional disturbances in cells. Alpine plant species are regularly exposed to freezing temperatures throughout the whole year. These species have learned to cope with freezing events and are, thus, of particular interest with respect to freezing survival mechanisms. Alpine plant species could serve as model organisms for freezing survival in creating means to improve frost tolerance in crops for their better performance in frost prone cultivation areas. In general, the understanding of freezing behaviour in plants could get even more important under the proposed climate change as ice nucleation temperatures and frost tolerance itself can be affected by increased CO2 concentrations and the rise in global mean temperatures is likely to cause premature bud burst and hence to increase the probability of spring frost damage.

Ice nucleation and propagation and resultant functional disturbances are studied at the cellular level using two new innovative technologies under field conditions. Freezing survival mechanisms are analysed in alpine plants as they have a large potential to act as model organisms for plant freezing tolerance in a metabolically active state. Freezing stress is an important environmental factor that limits the distribution of wild plants and crop species and can cause severe yield losses in agriculture. Therefore, understanding of freezing and how it damages plants is of extensive practical importance. Although current strategies for achieving understanding of freezing tolerance often focus on molecular analysis of cold acclimation, it is equally important to understand the freezing process itself. Knowledge of the exact mechanisms how plant tissues freeze is essential for developing rational strategies e.g. for conferring freeze-tolerance in species that have no tolerance of freezing. For studies of the freezing process in plants a recently invented, powerful technology, i.e. infrared thermography (IRT), offers the new possibility to determine frost tolerance mechanisms, i.e. supercooling or tolerance of extracellular ice, at the plant tissue level. IRT gives a real time image of the plant surface temperature, thus revealing the location at which ice first forms and showing the route and rate of initial growth of ice through the plant. An equally new method is the chlorophyll fluoroscence imaging technique , that allows in combination with IRT measurements to monitor the spread of intrinsic ice and concomitantly potential freezing induced functional disturbances in cells. Alpine plant species are regularly exposed to freezing temperatures throughout the whole year. These species have learned to cope with freezing events and are, thus, of particular interest with respect to freezing survival mechanisms. Alpine plant species could serve as model organisms for freezing survival in creating means to improve frost tolerance in crops for their better performance in frost prone cultivation areas. In general, the understanding of freezing behaviour in plants could get even more important under the proposed climate change as ice nucleation temperatures and frost tolerance itself can be affected by increased CO2 concentrations and the rise in global mean temperatures is likely to cause premature bud burst and hence to increase the probability of spring frost damage.