Seasonal changes of soluble carbohydrates in mycorrhizas of Norway spruce and changes induced by exposure to frost and desiccation

Abstract Mycorrhizas of six spruces of a stand were collected over two years and were analysed for soluble carbohydrates (sucrose, raffinose, glucose, trehalose and mannitol). The level of these carbohydrates was high during winter and low during summer. Upon exposure of excised mycorrhizas to frost or desiccation, the content of trehalose roughly doubled. A positive correlation was found between the trehalose content of mycorrhizas and their ability to survive frost or desiccation as determined by the electrolyte leaching method.