【摘要】 以PEG-6000模拟不同程度的水分胁迫对白刺幼苗进行处理,研究了其植株干重及其K+、Na+、丙二醛、游离脯氨酸、可溶性糖的含量变化.结果表明,15%PEG胁迫下白刺幼苗的生物量最高,丙二醛含量最低,且二者与对照的差异均显著;随着水分胁迫程度的增强,K+含量逐渐降低并与对照差异显著,Na+含量先减少后增加而其总积累量无显著变化;游离脯氨酸和可溶性糖含量随着水分胁迫程度的增强而显著增加.因此,轻度水分胁迫有利于白刺幼苗的生长,有机溶质游离脯氨酸和可溶性糖是白刺适应干旱环境的主要渗透调节物质.更多还原

【Abstract】 Nitraria sphaerocarpa seedlings were placed under different degrees of water stress simulated with PEG-6000 to investigate their variations in plant weights,and K~+,Na~+,MDA,free proline and soluble sugar contents.It was shown that under the water stress simulated with PEG-6000 at 15% Nitraria sphaerocarpa seedlings presented the highest biomass and the lowest MDA content and significantly differed from those under control in these two respects;as water stress was intensified,the seedlings gradually decreased their K~+ content and significantly differed from those under control in this respect,and they decreased their Na~+ content at the beginning and then increased the content but did not change their total Na~+ accumulation;and they significantly increased their free proline and soluble sugar contents as water became intensified.It follows that light water stress is favorable for Nitraria sphaerocarpa seedlings to grow,and free proline and soluble sugar are the major osmosis-regulating substances of Nitraria sphaerocarpa adapting to droughty environments among organic substances.更多还原