Elongation of wood fibers combines features of diffuse and tip growth

Xylem fibers are highly elongated cells that key constituents of wood, play major physiological roles in plants, comprise an important terrestrial carbon reservoir, and thus have enormous ecological economic importance. As they develop, from fusiform initials, their bodies remain the same length while tips elongate intrude into intercellular spaces. To elucidate mechanisms tip elongation, we studied cell wall along isolated, elongating aspen xylem used computer simulations to predict forces driving space formation required for growth. We found pectin matrix epitopes (JIM5, LM7) concentrated at where cellulose microfibrils transverse orientation, xyloglucan (CCRC-M89, CCRC-M58) fiber disordered. These features accompanied by changes thickness, indicating elongates strictly tips, it is deposited all over fibers. Computer modeling revealed needed intrusive growth may only require targeted release adhesion, which allows turgor pressure neighboring ‘round’ creating characteristics show fibers’ elongation involves a distinct mechanism combines both diffuse