Abstract: In order to improve the salt-tolerance and to increase planting area of oil sunflower,CaCl₂ regulation on salt-tolerance of oil sunflower under salt stress was studied, providing the theory basis for the comprehensive ut ilization of coastal beaches.The hybrid oil sunflower G101 as test materials was cultured in Hoagland nutrient solution.At the stage of four leaves,under salt stress the seedling was treated with 4,9,19,29 mmol/L CaCl₂ respectively.1/5 Hoagland nutrient solution and 1/5 of Hoagland nutrient solution containing 150 mmol/L NaCl was used as control.The effects of different CaCl₂ concentrations on seedling growth rate,net photosynthetic rate(Pn),superoxide dismutase(SOD),catalase(CAT),peroxidase( POD) activity and malonyldialdehyde(MDA) content of oil sunflower seeding under salt stress were measured.The results showed that oil sunflower seedling growth rate was decreased significantly under salt stress with 150 mmol/ L NaCl.However, treated with 5-30mmol/ L calcium,oil sunflower seedling growth rate were all improved and the net photosynthetic rate(Pn) of oil sunflower increased significantly.Especially under salt stress with 20 mmol/L calcium,the Pn were higher than that of control.under the condition of salt stress with 10 mmol/L calcium,the act ivity of SOD,POD and CAT were all increased and the MDA content were decreased in oil sunflower seeding.Therefore, based on the results,10 mmol/L CaCl₂ was considered as optimal concentration for regulating plant growth effectively under the salt stress with 150 mmol/L NaCl at seedling stage of oil sunflower.

Key words: Oil Sunflower, Salt stress, Photosynthetic rate, Growth rate, Antioxidant enzyme

CLC Number: 

• S565.01