Abating effects of exogenous Ca~(2+) on depressed seed germination and seedling growth of {\sl Kostelezkya virginica} resulting from NaCl stress

Seed germination and seedling growth of Kostelezkya virginica were studied with 1/4 Hoagland+0.5% NaCl as the basic nutrient solution whose CaCl_(2) concentration was set separately at 0,15,20,25,30 and 35 mmol/L,and the results showed that the seed germination rate gradually increased as the CaCl_(2) concentration increased.Where the CaCl_(2) concentration varied within 15--25 mmol/L,the K. virginica seedlings grew normally with their root vigor,chlorophyll content,and SOD and POD activities increased and their MDA content declined; where the CaCl_(2) concentration ranged within 30--35 mmol/L, the MDA content gradually rose and the other physiological parameters tended to gradually decline. It was shown that exogenous Ca~(2+) had abating effect on depressed seed germination and seedling growth of K. virginica and the best abating effect occurred with the CaCl_(2) concentration set at 25 mmol/L.