Altered Growth and Cell Walls in a Fucose-Deficient Mutant of <i>Arabidopsis</i>

A biochemical screening procedure was developed to identify mutants of Arabidopsis thaliana in which the polysaccharide composition of the cell wall was altered. Over 5000 ethyl methanesulfonate—mutagenized plants were analyzed by this method, leading to the identification of 38 mutant lines. One complementation group of mutants was completely deficient in L-fucose, a constituent of pectic and hemicellulosic polysaccharides. These mutant plants were dwarfed in growth habit, and their cell walls were considerably more fragile than normal.