KCl和NaCl对毕氏海蓬子生长和几种抗氧化酶活性的影响

Effects of KCl and NaCl on Growth and Several Antioxidative Enzyme Activities of Salicornia bigelovii Torr.

50～200 mmol·L^(-1)NaCl显著促进海蓬子生长和抗氧化酶[超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)]活性,与NaCl浓度相同的KCl明显抑制海蓬子生长和此3种酶的活性,但KCl下的超氧阴离子(O_2^-)和丙二醛(MDA)含量增加程度则明显高于同浓度的NaCl处理。据此认为,KCl伤害海蓬子的原因之一是抗氧化酶活性下降,不能及时清除活性氧,以致活性氧和MDA积累,引起质膜伤害,海蓬子生长受抑和生长量下降。

Halophyte Salicornia bigelovii was treated with different concentrations of KCl and NaCl. The results demonstrated that 50-200 mmol·L^-1 NaCl significantly enhanced the growth, superoxide dismutase （SOD）, peroxidase （POD） and catalase （CAT） activities of S. bigelovii. While the growth of S. bigelovii was markedly decreased when the plants were treated with 100-200 mmol·L^-1 KCl. KCl led to the decrease of SOD, POD and CAT activities. The superoxide anion （O2^-） and malondialdehyde （MDA） contents were increased markedly under 100-200 mmol·L^-1 KCl treatment contrasting with the same NaCl concentration. The results suggested that one reason for KCl toxicity was that the system of antioxidant enzymes could not scavenge the reactive oxygen species in time, which caused the accumulation of reactive oxygen species and the damage of membrane, which in turn caused the accumulation of MDA, so the growth of S. bigelovii was inhibited.