Scholarlink

Abstract <p>Cadmium (Cd) pollution, a toxic heavy metal ion pervasive in soil, water, and air, poses a major threat to plant growth and global ecosystems. In the present study, the effects of increasing Cd concentration on Cd bioaccumulation, polyamines (PAs) metabolism, antioxidant defense, and nutrient uptake were investigated in the sterile seedlings of <i>Potamogeton crispus</i> L. after 10 days exposure<i>.</i> The results revealed that Cd of exposure initially increased total putrescine (Put) and spermidine (Spd) levels at 80 µM but led to a decline in these compounds at higher concentrations, while spermine (Spm) levels decreased significantly. Cd stress also induced a continuous accumulation of free Put and reduced Spd and Spm contents. Thus, a significant decrease of total and free (Spd + Spm)/Put ratio became apparent. The effect of Cd application on perchloric acid soluble conjugated (PS-conjugated) PAs was similar to that seen for total PAs. With respect to perchloric acid insoluble bound (PIS-bound) PAs, Spd content increased, while Put and Spm levels declined. Enzymatic activities of arginine decarboxylase, ornitine decarboxylase, polyamines oxidase and diamine oxidase first increased and then declined, following the same trend. Additionally, the generation of superoxide anion (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\({\text{O}}_{2}^{{\bullet - }}\)</EquationSource> <!--PlntPhys2560488Shi-m1--> </InlineEquation>), hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), and malondialdehyde increased initially before decreasing. Antioxidant systems (superoxide dismutase, peroxidase, ascorbic acid, glutathione, soluble sugars, and proteins) mirrored the trends observed for <InlineEquation ID="IEq2"> <EquationSource Format="TEX">\({\text{O}}_{2}^{{\bullet - }}\)</EquationSource> <!--PlntPhys2560488Shi-m2--> </InlineEquation> and H<sub>2</sub>O<sub>2</sub>, while catalase activity rapidly increased. Nutrient levels of Cu, Zn, P, Mg, Fe, Ca, B, and Mn initially rose and then declined. These findings suggested that Cd-induced disturbances in polyamine metabolism, oxidative stress, and nutrient balance, and the altered polyamines, activated antioxidant system combined with increased nutrients could exert significant effects in the adaptation mechanisms of <i>P. crispus</i> under low Cd stress.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Effects of Cadmium Stress on Polyamine Content, Antioxidant Defense and Nutrient Uptake in Tissue-Cultured Potamogeton crispus L. Seedlings

  • 期刊论文

  • 发表日期：

    2026年1月23日

查看全文
  • X. M. Shi,
  • W. Y. Xie,
  • J. Shen,
  • Y. Tian,
  • X. Q. Qiao

摘要

Abstract

Cadmium (Cd) pollution, a toxic heavy metal ion pervasive in soil, water, and air, poses a major threat to plant growth and global ecosystems. In the present study, the effects of increasing Cd concentration on Cd bioaccumulation, polyamines (PAs) metabolism, antioxidant defense, and nutrient uptake were investigated in the sterile seedlings of Potamogeton crispus L. after 10 days exposure. The results revealed that Cd of exposure initially increased total putrescine (Put) and spermidine (Spd) levels at 80 µM but led to a decline in these compounds at higher concentrations, while spermine (Spm) levels decreased significantly. Cd stress also induced a continuous accumulation of free Put and reduced Spd and Spm contents. Thus, a significant decrease of total and free (Spd + Spm)/Put ratio became apparent. The effect of Cd application on perchloric acid soluble conjugated (PS-conjugated) PAs was similar to that seen for total PAs. With respect to perchloric acid insoluble bound (PIS-bound) PAs, Spd content increased, while Put and Spm levels declined. Enzymatic activities of arginine decarboxylase, ornitine decarboxylase, polyamines oxidase and diamine oxidase first increased and then declined, following the same trend. Additionally, the generation of superoxide anion ( \({\text{O}}_{2}^{{\bullet - }}\) ), hydrogen peroxide (H2O2), and malondialdehyde increased initially before decreasing. Antioxidant systems (superoxide dismutase, peroxidase, ascorbic acid, glutathione, soluble sugars, and proteins) mirrored the trends observed for \({\text{O}}_{2}^{{\bullet - }}\) and H2O2, while catalase activity rapidly increased. Nutrient levels of Cu, Zn, P, Mg, Fe, Ca, B, and Mn initially rose and then declined. These findings suggested that Cd-induced disturbances in polyamine metabolism, oxidative stress, and nutrient balance, and the altered polyamines, activated antioxidant system combined with increased nutrients could exert significant effects in the adaptation mechanisms of P. crispus under low Cd stress.