盐胁迫对菊花'紫燕翻飞'生长及生理特性的影响OA北大核心CSTPCD

To explore the physiological mechanism of chrysanthemum'Ziyanfanfei'response to salt stress,the effects of salt stress on its growth and physiological characteristics were studied in the experiment.Different concentrations(0,50,100,150,200 mmol/L)of NaCl treatments were set,and then their effects on plant height,leaf length,leaf width,shoot dry weight,root dry weight,ratio of root to shoot,and contents of malondialdehyde(MDA)and proline,activities of superoxide dismutase(SOD)and peroxidase(POD),relative electrical conductivity(REC),chlorophyll content and relative water content in leaves were analyzed.The results showed that with the increase of NaCl concentration,the plant height tended to decrease,the leaf length and leaf width had no significant change,the shoot dry weight and root dry weight tended to decrease,and the root-shoot ratio showed an increasing trend compared with the control(0 mmol/L NaCl).Under 50 mmol/L NaCl treatment,there were no significant differences in growth indexes compared with the control.Under 100,150,200 mmol/L NaCl treatments,the plant height,shoot dry weight and root dry weight signifi-cantly decreased compared with the control except the plant height treated with 100 mmol/L NaCl,while the root-shoot ratio increased significantly.The MDA content,REC and proline content in the leaves of'Ziyanfan-fei'gradually increased with the rise of NaCl concentration and the prolongation of treating time.The SOD and POD activities showed an obvious decreasing trend under the treatment of 50 and 100 mmol/L NaCl and the trend of increasing first and then decreasing under the treatment of 150 and 200 mmol/L NaCl,and those were all higher compared with the control.The chlorophyll content and relative water content of leaves showed the decreasing trends.The comprehensive analysis showed that the growth of chrysanthemum'Ziyanfanfei'was in-hibited by salt stress in a certain degree,but the plants could reduce the damage by increasing proline content and SOD and POD activities,so this chrysanthemum variety had a certain salt tolerance.