Cell-wall polysaccharides in growing poplar bark tissue.

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