NaCl胁迫对嫁接番茄根系质膜和液泡膜ATP酶活性的影响

在NaCl胁迫下，对番茄嫁接苗和自根苗的根系活力、根系质膜H+-ATPase、液泡膜H+-ATPase和H+-PPase、质膜和液泡膜Ca2+-ATPase、质膜氧化还原系统活性进行了比较。结果表明，胁迫条件下，嫁接苗根系活力显著高于自根苗。胁迫前期，嫁接苗根系质膜H+-ATPase活性、液泡膜H+-ATPase和H+-PPase活性、质膜和液泡膜Ca2+-ATPase活性、质膜NADH氧化速率和Fe (CN)63- 还原速率被显著诱导；自根苗根系液泡膜H+-ATPase、H+-PPase和Ca2+-ATPase活性、质膜NADH氧化速率和Fe (CN)63- 还原速率被显著诱导。胁迫后期，嫁接苗和自根苗根系各项指标均被显著抑制，但嫁接苗各指标受抑制时间较自根苗晚，且数值上均显著高于自根苗。表明嫁接苗比自根苗具有较强的耐盐性。

Effects of NaCl stress on ATPase activities of root plasma and tonoplast membranes in grafted tomato seedlings

The effects of NaCl stress on root vigor,H~ -ATPase activities of plasma membrane and tonoplast membrane, H~ -PPase activities of tonoplast membrane,Ca~(2 )-ATPase activities of plasma membrane and tonoplast membrane,plas- ma membrane redox system in roots of grafted and own-root tomato(Lycopersicon esculentum Mill.)seedlings were inves- tigated.Results showed that root vigor of grafted seedlings was significantly higher than that of own-root seedlings during the whole stage of stress.In the early stage of stress,H~ -ATPase activities of plasma membrane and tonoplast mem- brane,H~ -PPase activities of tonoplast membrane,Ca~(2 )-ATPase activities of plasma membrane and tonoplast mem- brane,NADH oxidation rate,Fe(CN)_6~(3-)reduction rate in roots of grafted seedling were significantly increased,H~ -AT- Pase,H~ -PPase and Ca~(2 )-ATPase activities of tonoplast membrane,NADH oxidation rate,Fe(CN)_6~(3-)reduction rate of own-root seedling roots were significantly increased as well.In the late stage of stress,the activities of all indices of both grafted and own-root seedlings were inhibited,but the inhibition of grafted seedlings was later and significantly lighter than those of own-root seedlings during the whole stage of stress.All these results indicated that the tolerance of grafted tomato seedlings to NaCl stress was stronger than that of own-root seedlings.