MITIGATION EFFECT OF CALCIUM ON THE GROWTH OF CUCUMBER SEEDLINGS UNDER NACL STRESS

The experiment was carried out to study the effect of exogenous Ca( NO3)2on the growth and physiological indicators of cucumber seedlings under Na Cl stress in nutrient solution culture. The results showed that 60 mmol·L- 1Na Cl stress significantly inhibited the morphological indicators and biomass accumulation of seedlings,the contents of photosynthetic pigments and ascorbic acid were significantly decreased,the membrane permeability,the contents of MDA,proline and soluble protein were significantly increased. Under salt stress,the contents of photosynthetic pigments and ascorbic acid of seedlings were significantly increased,membrane permeability and MDA content were significantly reduced,the contents of proline and soluble protein were furtherly increased,all growth indicators were improved in different extent by supplying different concentrations Ca( NO3)2. The performance of all indicators under 4 mmol·L- 1Ca( NO3)2treatment were superior to 2 mmol·L- 1and 6 mmol·L- 1Ca( NO3)2treatments. That research illustrated that exogenous Ca( NO3)2reduced the lipid peroxidation caused by Na Cl stress,alleviated the inhibition of seedling growth under Na Cl stress by regulating the synthesis of photosynthetic pigments in leaves,and enhancing the ability of antioxidation and osmotic adjustment,and the mitigation effect of 4 mmol·L- 1Ca( NO3)2treatment was best.