根施甜菜碱对盐胁迫下桑树幼苗生理生化反应的影响

Effects of Root-applied Glycinebetaine on Physiological and Biochemical Responses of Mulberry Seedlings Under Salt Stress

为探讨桑树的耐盐性栽培措施，对盐胁迫下桑树幼苗根施外源甜菜碱，调查不同处理下幼苗生长发育及相关生理指标的变化。结果表明，根施2.5～10.0mmol／L甜菜碱，可以提高盐胁迫（100mmol／L NaCl）下桑树叶片的叶绿素、可溶性糖和脯氨酸含量，保持叶片含水率，调节K^＋／Na^＋离子平衡，减少丙二醛含量，从而减轻盐胁迫对桑树生长的抑制作用；根施甜菜碱浓度以2．5～5．0mmol／L较为合适。

To explore possible cultivation measures for mulberry trees under salt stress, the changes in growth and physiological responses of mulberry seedlings were investigated by applying 2.5～10.0 mmol/L glycinebetaine through root system under 100 mmol/L NaCl stress. The results showed that exogenous glycinebetaine increased the contents of chlorophyll, soluble sugars and proline in leaves, maintained the leaf water content, regulated K^＋/Na^＋ ion equilibrium, reduced the content of MDA, and thereby alleviated the inhibition of mulberry growth under salt-stress. Moreover, it was found that the glycinebetaine concentration at 2.5～5.0 mmol/L was suitable for root application.