Abstract: To explore the physiological response of Malus sieversii to salinity stress, Malus sieversii seedlings were cheared with six salinity levels (0,0.2%,0.4%,0.6%,0.8% and 1.0% NaCl) for 4 hours and seven time levels (0,4,8,12,16,20 and 24 hours) in 0.4% NaCl.Contents of proline,MDA,chlorophyll,and soluble sugar in leaves and activity of SOD and POD were mensurated.The results showed that proline content got the peak when NaCl concentration was 0.6% or 12 h in 0.4% NaCl,increasing 63.1% and 27.0% compared to control respectively.Increasing salt concentration and time resulted in higher levels for malondialdehyde content.Chlorophyll content was decreased first,subseguently increased and decreased once more.Among all treatment they were lower than control.Soluble sugar content and the activity of SOD and POD were increased first,then decreased.The results indicated that Malus sieversii could reduce the damage to the plant by accumulating more proline and soluble sugar and increasing the activity of SOD and POD.It was adapted to salinity stress to some extent.

Key words: Malus sieversii, Salinity stress, Antioxidant enzymes, Physiological responses

CLC Number: 

• S5661.01