盐胁迫对国槐和中林46杨幼苗膜类脂的影响

Effect of salinity on membrane lipids in pagoda tree and poplar ‘zhonglin-46'.

通过薄层层析法和气相色谱法研究盐胁迫前后国槐 (Sophorajaponica)和中林 46杨 (Populusxeuramericana(Dode)GuinerCL .‘zhonglin 46’)幼苗叶和根系生物膜类脂组成的变化 ,揭示生物膜类脂在树木抗盐方面的作用 .结果表明 :盐胁迫后国槐叶的磷脂含量上升 ,中林 46杨叶磷脂含量略有下降 .这两个树种生物膜磷脂的最大差别是盐胁迫前后中林 46杨叶和根系PC PE的比值明显高于国槐 ,并且中林 46杨叶和根的总极性脂的不饱和指数都大于国槐的叶和根 ,说明中林 46杨生物膜的流动性大于国槐的 .并且在盐胁迫后中林 46杨根的极性脂脂肪酸的饱和水平只增加1 3 2 3 % ,而国槐叶的极性脂脂肪酸的饱和水平增加 34 49% .这些差异是导致盐胁迫后中林 46杨叶中Na+和Cl-含量比国槐叶中的Na+和Cl-含量高的原因之一 ,也是导致中林 46杨比国槐抗盐能力弱的原因之一 .

Membrane lipids of leaf and root from salt stressed pagoda tree ( Sophora japonica )and poplar ‘zhonglin 46'( Populus×euramericana (Dode) Guiner CL. ‘Zhonglin 46') seedlings were studied by thin layer chromatography and gas chromatography to disclose the role of membrane lipids played in salt resistant capacity of woody plants. Results are as follows: the content of phospholipid of leaf from pagoda tree increased after salt treatment, while that from poplar ‘zhonglin 46' decreased a little. Membrane fluidity of poplar ‘zhonglin 46' was larger than that of pagoda tree. It was due to that PC/PE ratios and unsaturated fatty acid index of polar lipid from leaf and root in poplar ‘zhonglin 46' were larger than those in pagoda tree respectively before and after salt stress. In comparison with the control, lipid saturated fatty acid levels of leaf from poplar ‘zhonglin 46' increased by 13 23%, while that of leaf from pagoda tree gained by 34 49 % after salt treatment. All the above differences led to the higher content of Na + and Cl -in leaves of poplar ‘zhonglin 46' than that of pagoda tree. The differences also were the reason why the resistant capacity of pagoda tree was larger than that of poplar ‘zhonglin 46'.