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  • 1 Agricultural University, al. 29 Department of Biochemistry Cracow Poland 31-425 Listopada 54 Cracow Poland 31-425 Listopada 54
  • 2 Agricultural University, al. 29 Department of Ornamentals Cracow Poland 31-425 Listopada 54 Cracow Poland 31-425 Listopada 54
  • 3 Jagiellonian University Division of Advanced Materials Engineering, M. Smoluchowski Institute of Physics Cracow Poland 30-059 ul. Reymonta 4 Cracow Poland 30-059 ul. Reymonta 4
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Abstract  

The DSC method was used to study phase transitions in Rhododendron L. leaf tissues caused by temperatures below the freezing point of water. The curves show several stages of water crystallisation, demonstrating that these processes do not occur simultaneously in various types of cell organelles. Temperatures and enthalpies of the phase transitions were determined and significant changes were found in the DSC curves when the sample was repeatedly subjected to sub-zero temperature cooling and heating. Also, frost resistance of the same rhododendron taxons was studied by conductometric analysis and the DSC results were compared with the data from other laboratory studies.