Cold-Acclimation Associated Changes of Soluble Carbohydrates in Mycorrhizal and Non Mycorrhizal Roots of Picea Abies Inoculated with Pisolithus Tinctorius

Abstract

Both mycorrhizal and non mycorrhizal roots of Norway spruce accumulated the trisaccharide raffinose when the plants were kept at low temperature and a short photoperiod. More raffinose was accumulated at low light intensities (18μE m^-2s-¹) than at high light intensities (300μE m^-2s^-1). Conversely, the level of sucrose, the main soluble carbohydrate present in the roots, increased in mycorrhizal and non mycorrhizal roots at the high light intensities whilst it decreased slightly at low light intensities during the cold treatment. The main fungal soluble carbohydrates found in the mycorrhizal roots were trehalose, arabitol and mannitol. Under low light intensities in the cold the level of arabitol decreased, whereas the levels of trehalose and mannitol remained constant and slightly increased, respectively. However, under high light intensities, the amounts of all the fungal soluble carbohydrates increased, particularly arabitol and trehalose.