Abstract: The progress on the structure and physiological functions of apoplastic barriers in root is presented for recently ten years. The apoplastic barriers consist of the cell wall with Casparian bands, suberin lamellae or lignin which showed as protective tissue, that tight block water, ion and oxygen between plant and environment. The molecular information of Casparian bands indicated the endodermis similar to tight junctions of epithelial barrier. The apoplastic barriers are the key structure for plant adapted to adverse environment that guarantee various physiological and biochemical reactions processing under steady inner surroundings. The apoplastic barriers reacted well to drought, flooding, ion deficiency, and disease stresses, and broadly applied to explore plant resource to adapt and restore the extreme environment.

Key words: apoplastic barriers, anatomical structure, histochemistry, spatiotemporal development, permeability