Leaf senescence induced by sodium chloride was studied in Hydrocotyle bonariensis Lam. and Foeniculum vulgare L. Both species belong to Umbelliferae family, however only H. bonariensis grows spontaneously in sandy soils of coastal regions (saline soils). Leaves of plants receiving nutrient solutions containing different concentrations of NaCl were evaluated for fresh and dry weights and chlorophyll content. The denaturating electrophoretic profiles of leaf proteins were also studied. Sodium chloride changed the protein profile of F. vulgare and hastened the leaf senescence of both the species. However, plants of H. bonariensis receiving 599 mM NaCl lasted longer than F. vulgare. Therefore, the occurrence of H. bonariensis in saline soils might be related with mechanisms of salinity tolerance.
chlorophyll; protein; salinity; senescence
