铬胁迫对罗汉果幼苗生理生化指标的影响

The Effect of Chromium Stress on Physiological and Biochemical Parameters of Siraitia Grosvenorii Seedings

重金属铬对植物的生长发育有着非常重要的抑制作用。但是至今为止,铬对中国特有药用植物罗汉果的生理生化影响的研究报道几乎没有。本实验以罗汉果幼苗为材料,研究了在不同浓度重金属铬离子培养基(0、50、100、150、200μmol/L)中生长15天的罗汉果幼苗的相关生理生化指标及其变化。结果表明,随着铬离子浓度的增加,植株叶片的叶绿素含量、蛋白质含量、可溶性糖含量、超氧物歧化酶活性、过氧化氢酶活性一直下降;过氧化物酶活性先上升后下降;相反,脯氨酸和丙二醛含量则一直上升。铬离子的毒害导致体内保护酶活性受到抑制,膜系统受到伤害,从而影响了罗汉果幼苗的生长。在植物对铬离子的反应过程中,脯氨酸和活性氧信号可能起着非常重要的作用。

Heavy metal chromium markedly inhibits plants growth and development.Although extensive studies have been conducted on the effects of chromium on other plant species such as wheat,effects of chromium on Siraitia Grosvenorii remain unknown.In this paper,the author studied physiological and biochemical parameters of Siraitia Grosvenorii under different levels of Cr 6 + (0,50,100,150,200 μ mol/L).The results showed that the contents of chlorophyll,protein,soluble sugar,activity of superoxide dismutase (SOD) and catalase were significantly decreased with increasing concentrations of chromium;the levels of peroxidase (POD) activity were increased at low concentrations of chromium and decreased when the plants were exposed to high concentrations of chromium.By contrast,the contents of proline and malonaldehyde (MDA) were substantially increased with increasing concentrations of chromium in the growth medium.The results indicated that chromium caused damage of the celluar membrane system and inhibition of activity of protective enzymes,which affected growth of Siraitia Grosvenorii seedings.Proline and reactive oxygen species (ROS) signaling might play important roles in plant responses to chromium.