Antioxidant Responses of Helianthus annuus L. under Vanadium Stress.

Subject Areas : Stress Physiology

Masoumeh  Abedini ¹ (Faculty of Basic Sciences, Payame Noor University, Iran)
Fatemeh Mohammadian  Fatemeh Mohammadian ² (Faculty of Basic Sciences, Payame Noor University, Iran)
Behrokh  Daie-Hassani ³ (Faculty of Basic Sciences, Payame Noor University, Iran)
Leila  Zarandi-Miandoab ⁴ (Department of Biology, Faculty of Basic Sciences, Azarbaijan Shahid Madani University, Tabriz, Iran)

Received: 2017-03-14 Accepted : 2018-03-14 Published : 2017-10-01

Keywords: MDA, Proline, Helianthus annuus, H2O2, free amino acids, Antioxidant enzymes,

Abstract :

Vanadium (V) is a transition metal consistently distributed in the Earth’s crust. At trace concentrations, it has been described as a beneficial element for some organisms; however, it is toxic at higher concentrations. This study was conducted hydroponically in a complete randomized design to investigate effects of V (0, 3.25, 7.5, and 15 mg L-1) on antioxidant system of sunflower. Results showed that all applied concentrations of V significantly decreased the plant growth, but increased the free amino acids, proline, malondialdehyde and H2O2 contents of plants. The antioxidant enzymes activities increased in response to the increase in V concentration. The activity of (Guaiacol) peroxidase showed a significant increase at 15 mg L-1 V while the activities of catalase, glutathione reductase, and ascorbate peroxidase decreased significantly by application of V. There was a slight increase in the superoxide dismutase activity at different concentrations of V. The study concludes that the applied concentrations of V induced oxidative stress in sunflower and (Guaiacol) peroxidase was a more effective antioxidant enzyme in scavenging the free radicals in this plant.