Effect of NaCl on some physiological parameters in sunflower (Helianthus annuus L) seedlings

Excess NaCl in the growth medium of sunflower seeds (Helianthus annuus L.) affected germination and seedling growth, and altered the absorption and distribution of the Na ion. At a low dose of NaCl (25 mM), seedling growth, but nor foliar surface, increased. Foliar surface was more markedly affected than accumulation of dry matter in the leaf by treatment with all doses of salt. The root was more markedly affected by saline conditions than the aerial part. Sodium ion accumulation at low and moderate (50 mM) salinities was greater in aerial parts than in the root, whereas the opposite finding was obtained at high (100 mM) salinity. Chloride content was always higher in the root than in the aerial part at the three saline levels tested.