Research themes
● Structure and function of woody cell wall
Electron microscopic studies of cell wall structure,
e.g., fine structure and function of pits in tracheary elements
Wood structure viewed under a scanning electron microscope
● Structure, properties and function of bark
Anatomical studies of basic structure, formation and secondary changes in the structure of bark; collecting basic data concerning physical properties and mineral contents of bark
Bark of Picea glehnii
● Wood identification
Identification of archaeological wood remains unearthed at historical sites in Hokkaido for better understanding of the wood utilization by ancient people
Scanning electron micrographs showing charred wood, which was used for timber of pit dwelling unearthed on the campus of Hokkaido Univ. (Sano and Watanabe 2003）
● Overwintering mechanism
From autumn to winter, many morphological and physiological changes occur in trees growing in Hokkaido with development of high freezing resistance. In winter, all living cells avoid freezing of intracellular water by ways which are dependent on tissues and organs.
Extraorgan freezing in winter bud of larch.
Shoot primordia tissues are isolated from excluded from extracellular ices which are accumulated in ice sink in winter buds.
● Regulation of freezing of water
Some polyphenols have activities that decline freezing temperature of water by inhibition of ice-nucleation activities, resulting in maintenance of supercooling state of water. This activity may be used for frost damage prevention of crops.
● Preservation of genetic resources of trees
Cryopreservation method is examined to preserve the genetic resources of trees such as transgenic poplars.
