Effects of NaCl Stress on Physiological and Biochemical Characteristics of Pitaya (Hylocereus undatus) Seedlings
The cutting potted pitaya was used as the material for the study on the changing tendency of physiological index in the tender stem under NaCl stress.The results showed that: The physiological index of pitaya tender stem did not change significantly in the period of 0~14 d,but changed greatly after 28 d when under stress of 0.4% NaCl;The relative conductivity,contents of MDA and soluble saccharides,and the activity of SOD,POD and CAT were significantly increased under stress of 0.8% NaCl,but Pro contents changed erratically;Under stress with 1.2% NaCl,the relative conductivity,contents of MDA and Pro were significantly increased;The contents of soluble saccharides showed the trend of declining-rising-declining.And the SOD,POD and CAT activity raised up remarkably,but the activity was decreased when reached the peak after 14 ~21 d;The physiological and biochemical indices of plants not changed obviously at the Na+concentration of 5 mg/g in soil indicated that pitaya had stronger salt tolerance.