低温下硼对巨尾桉叶片膜脂过氧化及体内保护系统的影响

Effects of Boron on Membrane Lipid Peroxidation and Endogenous Protective Systems in Leaves of Eucalyptus grandis × Eucalyptus urophylla under Low Temperature

摘要:

以木本植物巨尾桉幼苗为材料,研究在低温下,硼对巨尾桉叶片膜脂过氧化及体内保护系统的影响。结果表明:在低温(5℃,以25℃为对照)下,缺硼或低硼(≤10 μmol/L)导致巨尾桉叶片相对电导率、超氧物阴离子自由基(O₂^-.)产生速率、丙二醛(MDA)含量和多酚氧化酶(PPO)活性增加;抗坏血酸(ASA)和可溶性蛋白质含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性下降。而15 μmol/L硼可以减轻低温对巨尾桉幼苗的伤害,提高巨尾桉幼苗的抗寒能力。

Abstract:

Eucalyptus grandis×Eucalyptus urophylla seedlings were used as materials to study the effects of boron on membrane lipid peroxidation and endogenous protective systems in leaves under low temperature. The results showed that relative conductivity rate, O₂^-. production rate, malondialdehyde (MDA) content and polyphenol oxidase (PPO) activity in leaves were increased at 5℃ with boron-deficiency (≤10 μmol/L). On the contrary, the contents of ascorbate (ASA) and soluble protein, the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were decreased. However, addition of 15 μmol/L boron in the culture medium could alleviate chilling injury and enhance the tolerance to low temperture in the seedlings.