Abstract | Plant root cells elongate anisotropically with deposition of new material and modification of cell wall properties occurring over the entire wall (with the exception of root hairs which exhibit tip growth). This anisotropic growth pattern is dependent on directional mechanical properties of the cell wall, conferred by a tightly regulated network of cellulose microfibrils embedded in the wall matrix. Experimental techniques to analyse the structure of the elongating cell wall and the potential mechanisms whereby walls are modified will be presented, together with techniques to parameterize current models for the control of cell expansion in roots. |