Effect of Submergence on the Cell Wall Composition of Deep-Water Rice Internodes

The cell wall composition of internodes of deep-water rice plants (Oryza sativa L. cv Habiganj Aman II) which were induced to grow rapidly by submergence in water was compared to that of nonsubmerged plants which grew slowly. No differences could be detected in cellulose, uronic acid, and lignin content expressed on a dry weight basis. Cell wall preparations of rapidly growing, submerged internodes contained more hydroxyproline and had a higher hydration capacity than those of control internodes. The silicon content of submerged rice internodes was considerably lower than that of air-grown plants. The role of silicon as a structural component of the cell wall of grasses is discussed in relation to lodging of deep-water rice plants after the flood waters have receded.