Effects of nitric oxide on the growth and antioxidant response of submerged plants hydrilla verticillata (l.f.) royle

Abstract

To investigate the effect of exogenous Nitric oxide (NO) on submerged plants, Hydrilla verticillata (L.f.) Royle was treated with 25 - 400 μM sodium nitroprusside (SNP, a NO donor) for 0.5 - 4 d. The alterations in plant growth, H2O, total chlorophyll and malondialdehyde (MDA) content and the antioxidant response were assayed. The results showed that 25 - 100 μM SNP increased the plant growth and total chlorophyll content and reduced the level of H2O. However, an increase in H2O and MDA content and a decrease in total chlorophyll were detected in plants exposed to 200 - 400 μM SNP. The activity of catalase and peroxidase decreased in plants exposed to 25 - 400 μM SNP; and for superoxide dismutase, its activity was suppressed by the 25 and 50 μM SNP. The content of ascorbic acid and dehydroascorbate were also determined. The results provided the evidence that 25 - 100 μM SNP increased the growth of H. verticillata by alleviating the oxidative stress and 200 - 400 μM SNP might enhance the oxidative stress in plant cell. The results suggested that NO has dual role on the growth and ROS metabolism of Hydrilla verticillata (L.f.) Royle. © 2010 Academic Journals.