Abstract
Salicornia herbacea is one of the halophytes whose growth is promoted by the presence of NaCl. In this study, we investigated parameters regulating the growth of hypocotyl in Salicornia seedlings treated with NaCl under continuous light or dark conditions.
Hypocotyl elongation of Salicornia seedlings was promoted by the addition of 100 mM NaCl in both continuous light and dark conditions. Viscous and elastic extensibility of cell wall in the hypocotyls of both light-grown and dark-grown seedlings were decreased by the exposure to 100 mM NaCl. The content of pectin in cell wall of hypocotyls was significantly decreased in seedlings treated with 100 mM NaCl under continuous light conditions. On the other hand, the content of pectin and hemicellulose in cell wall of hypocotyls were decreased in dark-grown seedlings treated with 100 mM NaCl.
These results suggest that NaCl reduces the content of polysaccharides such as pectin and hemicellulose of the hypocotyl cell walls, and increases the extensibility of hypocotyl cell wall as a result of decrease of the viscosity in Salicornia.
