Changes of Osmotic Adjusting Substances in Leaves of Tamarix chinensis Seedlings under Salt and Drought Stress

To research the suitability of Tamarix chinensis seedlings to salt and drought stress,we studied the contents of osmotic adjusting substances in leaves of two years old T.chinensis seedlings under salt and drought stress by pot culture.The results showed that:(1)The soluble sugar content increased and then decreased with the stress intensified and kept higher than that of control under moderate and severe salt and drought stress.(2)The proline content increased with the stress intensified,but only significantly higher than that of control under the intercross stresses of severe salt and moderate and severe drought.(3)The contents of Na+ and Cl-changed irregularly,and kept a significantly higher level than that of control under different stresses.(4)The contents of K+,Ca2+ and SO42-decreased with the salt stresses intensified under light and severe drought stresses.Under moderate drought and salt stresses,the contents of K+ and Ca2+ had no difference with the control.Therefore,the osmotic adjusting substances played an active role on salt and drought resistance.In conclusion,T.chinensis seedlings showed some tolerance to salt and drought stresses,and appropriate drought stress could increase the resistance of T.chinensis to salt stress.