QUANTIFICATION OF SUGAR CONTENT IN THREE BRYOPHYTE SPECIES DURING SALT STRESS

Abstract

Sugars are known to be involved in desiccation tolerance in bryophytes. However, a few studies discussed their function in other types of abiotic stresses such as salt stress. The aim of this research was to identify and quantify sugars which participate in the response to exogenous NaCl of three bryophyte species, namely model moss Physcomitrella patens and bryo-halophytes Entosthodon hungaricus and Hennediella heimii . Besides quantification of sugar content by HPLC-PAD analysis, the aim was to reveal localization of complex sugars in the protonema and phylloid cells using histochemical staining method. Among 23 sugars and sugar alcohols tested, monosaccharides glucose and fructose and disaccharides sucrose were present in the highest concentrations in each tested species. During the exposure to NaCl, concentrations of sugars change in a species -specific manner. There are certain similarities between model moss and bryo-halophyte H. heimii such as increase of galactose, maltose, trehalose and galactitol, suggesting similarities in the mechanisms of salt resistance. Bryo-halophytes seem to use different