Abstract:

The seeds of barley ( Hordeum vulgare L. cv. Jian 4) were soaked with 0.1 mmol/L putrescine (Put) and 0.5 mmol/L spermidine (Spd), and then the seedlings were treated with 200 mmol/L NaCl. The growth rate (GR), dry matter accumulation, distribution of ions, the amount of polyamines (PAs) bound to tonoplast proteins as well as lipid composition and the activity of tonoplast vesicles isolated from roots were investigated. The results showed that soaking with Put or Spd could retard salt injury, promote GR and dry matter accumulation, and increase K+/Na+ in the roots. Compared with NaCl treated plants, phospholipid content in root tonoplast rose by soaking with Put and Spd, while the level of galactose in lipids was decreased. Moreover, the ratio in noncovalently conjugated PA contents of (Spd+PAx (an unknown PA)) to (Put+Dap (diaminopropane)), and the total contents of covalently and noncovalently conjugated PAs were all increased. Statistical analysis indicated that the ratio of （Spd+PAx）to (Put+Dap) was significantly and positively correlated with the activities of membrane associated enzymes H+ ATPase and H+ PPase.

多胺浸种改善盐胁迫大麦根系液泡膜功能的机理
孙 诚 刘友良* 章文华
（南京农业大学，农业部作物生长调控重点实验室，南京210095）

摘要: 研究了0.1 mmol/L 腐胺 (Put) 和0.5 mmol/L 亚精胺 (Spd) 浸种对200 mmol/L NaCl胁迫下大麦(Hordeum vulgare L.)幼苗生长速率、干物质积累、离子分布、液泡膜蛋白结合多胺含量以及液泡膜膜脂组分与功能的影响.结果表明,Put和Spd浸种均可缓解盐胁迫对大麦幼苗的盐害,促进生长和干物质积累,降低大麦幼苗体内[Na+]/[K+].与盐处理的对照植株相比,Put和Spd浸种均可提高大麦幼苗根系液泡膜磷脂含量,降低糖脂结合半乳糖含量,而膜上非共价结合多胺含量Spd+PAx (一种未知多胺) 与 Put+Dap (二氨基丙烷)之比((Spd+PAx)/(Put+Dap))、共价和非共价结合多胺总量均上升.统计分析结果表明,液泡膜非共价结合多胺(Spd+PAx)/(Put+Dap)与H+-ATPase和H+-PPase活性呈显著正相关关系.

关键词： 大麦；盐胁迫；多胺；膜脂；膜结合酶

通讯作者。E-mail: zwslsh @ public l.ptt.js.cn

Key words: barley, salt stress, polyamines, membrane lipids, membrane associated enzyme