Seasonal Changes in Sugar and Starch Content of the Alpine Snowbed Plants, Primula cuneifolia ssp. hakusanensis and Fauria crista-galli, in Japan

Growth periods of Primula cuneifolia ssp. hakusanensis and Fauria crista-galli, the snowbed plants, were shorter than those of most alpine plants. Primula cuneifolia ssp. hakusanensis showed a larger seasonal change of starch than that of sugar content in both aboveground and belowground organs. On the other hand, in Fauria crista-galli sugar content and its seasonal change were always larger than those of starch. A relatively high content of sugar in Fauria crista-galli during the cold season seems to protect against freezing in winter. Winter buds of both species and new roots of Primula cuneifolia ssp. hakusanensis were formed in the cold season. It is suggested that snowbed plants have a specific amylase which is active in severe low temperature.