外源油菜素内酯对番茄铜胁迫的缓解效应

Exogenous EBR on alleviating copper stress in tomato seedlings

采用营养液水培的方法,以"改良毛粉802F1"番茄为材料,研究外源2,4-表油菜素内酯(2,4-EBR,简称EBR)对铜胁迫下番茄抗氧化酶系统及生长发育的影响。结果表明,与铜胁迫处理相比,外源EBR处理能显著激活铜胁迫下抗氧化酶系统[过氧化物酶(POD)、超氧化物岐化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)]和根系活力,使丙二醛含量明显降低,叶绿素含量和生物量显著升高;铜胁迫显著提高了番茄铜含量(尤其是根系),而外施EBR能够显著降低铜胁迫下番茄叶片和根系铜的含量,提高带有相同电荷的竞争性离子Fe、Zn、Mn含量,利于养分平衡,维持番茄正常的生长代谢。

Through nutrient solution cultivating in greenhouse, the tomato cultivar, Gailiang Maofen 802F1, was selected as the plant material to investigate the effects of 2,4 -EBR on anti-oxidizing enzyme system and growth under copper stress. The results show that the exogenous EBR could effectively improve the activities of anti-oxidizing enzyme systems （POD, SOD, CAT, APX） in leaves and root activity under the copper stress, while the MDA content is remarkably reduced. As an effect of a long period, the content of chlorophyll and plant weight are significantly increased. For mineral elements, excessive copper obviously enhances the copper uptake and transplant in tomato plant, while the exog- enous EBR could remarkably reduce the copper content and increase the contents of Fe, Zn and Mn, which take the same electric charge and are competitive restrain with copper ion in transmembrane transport. The above phenomenon might help the nutrient balance and normal growth metabolism of tomato. In conclusion, the exogenous EBR could allevi- ate growth restrain of tomato seedlings through adjusting the activities of anti-oxidizing enzymes and ion homeostasis under the copper stress.