Hg污染胁迫对葡萄果树生理特性的影响

摘要

[目的]研究Hg污染胁迫对葡萄果树生理特性的影响.[方法]通过盆栽试验,研究不同浓度汞胁迫下葡萄果树细胞膜透性、游离脯氨酸含量、MDA含量及SOD、POD、CAT保护酶活性在不同生长发育期的变化规律.[结果]随着土壤汞浓度的增加,葡萄叶片相对电导率、MDA含量、游离脯氨酸含量以及SOD活性均逐渐升高.POD活性则呈现出随Hg浓度增加先升高后降低的变化趋势.CAT活性却随汞浓度增加而下降.在葡萄不同的生育时期,相对电导率和MDA含量随葡萄果树生长而减少,其顺序为成熟期＞转色期＞幼果生长期＞开花期,游离脯氨酸含量和SOD活性则呈现出相反的顺序,即开花期＞幼果生长期＞转色期＞成熟期,POD活性随时间的变化顺序为转色期＞幼果生长期＞开花期＞成熟期,CAT活性随时间的变化顺序则是幼果生长期＞转色期＞开花期＞成熟期.[结论]葡萄植株在较短生长期内对低浓度Hg有较强的抵御能力,而在较长生长期内对高浓度Hg的抵抗力下降,并受到Hg污染的严重伤害.%[Objective]The research aimed to study the effects of hydrargyrum stress on physiological indexes of grape plants. [Method]Grapes was planted in pot and different content of hydrargyrum was added to soil. The chang of cell membrane permeability, proline contents,MDA content and SOD,POD,CAT activities in grape leaf in different cultivation times were analyzed. [Result] With the inerease of Hg content in soil,relative electric conductivity,MDA content,proline content and SOD activity in leaves of grape increased. POD ativity increased first and then decreased. Hg obviously inhibited CAT activity. In different cultivation times, relative electric conductivity and MDA content decreased with the growth of grape trees. It showed in an order of flowering period < young fruit growth period < turn color period < mature period. Proline content and SOD activity showed in the opposite order, namely flowering period > young fruit growth period > turn color period > mature period. POD activity showed mature period < flowering period < young fruit growth period < turn color period, while CAT activity showed young fruit growth period > turn color period > flowering period > mature period. [ Conclusion ] Lower concentration of Hg can increase the endurances of grape plants in short term. But with the higher concentration and the extension of time, the effect will decrease,even the growth will be inhibited.