Abstract:Effects of CaCl2 concentration on the changes of morphological and physiological characteristics were investigated using Orostachys malachophyllus as experimental material.The result showed that when concentration of CaCl2 ranged from 5 to 10 mmol/L,leaf color was dark green and plant types were compacted.The diameter of crown,leaf area and length of root increased a little more than that of the control.The content of chlorophyⅡincreased compared with that of the control but other physiological indices showed no significant difference.Under the treatment of 20 mmol/L CaCl2,leaf area was approximate and length of root increased,but diameter of crown decreased with no significant difference.Electrical conductivity,MDA content and the activities of antioxidant enzymes including SOD,POD,CAT increased,while relative water and content of chlorophyⅡwere a little less than that of control.Under the treatment of 40 and 50 mmol/L CaCl2,leaf color became yellow and plant types got loosed.Diameter of crown,leaf area and length of root decreased remarkably.Electrical conductivity,MDA Content,antioxidant enzymes increased remarkably but relative water and content of chlorophyⅡdecreased remarkably.These results showed that Orostachys malachophyllus can tolerance 5 to 20 mmol/L CaCl2 with nutrient solution especially better under the treatment of 5 to 10 mmol/L.But more than 20 mmol/L CaCl2 was added to the nutrient solution,the plant growth was significantly inhibited.