Abstract: In a pot experiment with the nutritional medium made by seaside saline-alkali soil,this paper studied the growth and root development of salineresistant transgenic (mtk-D gene) Zhongtian poplar in cutting propagation.The results showed that the survival rate and growth of the cuttings decreased with increasing soil salt content.In the treatment of 2 g·kg^-1 salt content,the cuttings had a survival rate of >90%,and grew normally.When the salt content was >4 g·kg^-1,the cuttings died gradually because of salt stressinduced injuries,and the phloem lateral roots became brown and died,which resulted in the yellowing,wilting and dying of leaves.No significant difference was found in the salt tolerance and growth between saline resistanttransgenic Zhongtian poplar and its original wild type at the early stage of cutting propagation,which was probably related to the expression of the transgene in the cuttings.

Key words: Hydraulic engineering, River ecosystem, Ecosystem services, Assessment approaches