CELL-WALL POLYSACCHARIDES IN GROWING POPLAR BARK TISSUE

In order to study changes in the cell-wall composition of growing popl ar cambium during the seasonal cycle, cell walls were isolated from th e cambium and newly formed vascular tissues of poplar branches at thre e times during the year (winter, beginning of spring, end of summer). Polysaccharide material was isolated by sequential extraction of the c ell walls and analysed. The principal polysaccharides identified were pectins and xylose- and glucose-containing polysaccharides, possibly x ylans and (xylo)glucans. Our results indicate changes in the relative quantities of these polysaccharides during the seasonal cycle.