伽蓝菜和碱蓬耐旱耐盐机理的比较研究

Comparative studies on the mechanisms of salt tolerance and drought tolerance of Kalanchoe daigremotiana and Suaeda salsa

分别用 0～ 2 0 0 mmol/L Na Cl和等渗的 PEG(聚乙二醇 )处理伽蓝菜和碱蓬幼苗 ,测定结果表明 :伽蓝菜的生长明显受 Na Cl和等渗的 PEG抑制 ,PEG处理比等渗的 Na Cl处理对伽蓝菜生长的抑制更显著 ;碱蓬的生长明显受 Na Cl促进 ,而等渗的 PEG抑制其生长。 Na Cl处理条件下碱蓬叶片内 Na+、Cl-含量显著高于伽蓝菜 ,而 PEG处理条件下伽蓝菜叶片内有机溶质含量高于碱蓬。 Na Cl和 PEG处理条件下伽蓝菜蒸腾速率降低幅度远远大于碱蓬。这些结果说明 ,伽蓝菜耐旱的机制主要是通过减小自身鲜重进行渗透调节 ,而碱蓬耐盐的机制主要是吸收 Na+。

Kalanchoe daigremotiana and Suaeda salsa seedings were treated with 0 200mmol/L NaCl or isotonic PEG(polyethyleneglycol)solution for seven days.Results showed that the growth of Kalanchoe daigremotiana was inhibited by both NaCl and isotonic PEG and it was inhibited more severely by PEG solution than by isotonic NaCl solution.On the contrary,the growth of Suaeda salsa was improved by NaCl,but it was also inhibited by PEG.The content of Na +、Cl - in the leaves of Suaeda salsa was higher than that of Kalanchoe daigremotiana under NaCl solution,while the content of organic compatible solutes in the leaves of Suaeda salsa was lower than that of Kalanchoe daigremotiana under PEG solution.The transpiration rate of kalanchoe daigremotiana decreased more quickly under both NaCl solution and PEG solulion than that of Suaeda salsa. This result suggestted that the mechanism of drought tolerance of Kalanchoe daigremotiana was mainly by reducing fresh weight to perform osmotic adjustment,while the mechanism of salt tolerance of Suaeda salsa was mainly by absorbing Na +、Cl - and accumulating them in vacuoles to perform osmotic adjustment.