Induction of Glutathione, Ascorbate and Associated Enzymes by a Low Dose CdCl2 Pre-treatment Alleviate Fusarium Induced Oxidative Stress in Wheat

Induction of glutathione (GSH), ascorbate (ASC) as well as their associated enzymes have been investigated in co-stressed (50 μM CdCl2 pre-treatment followed by Fusarium infection) wheat
seedlings. An enhanced GSH content, GSH/GSSG ratio and ASC content was observed in co-stressed tissues as compared to Fusarium infected tissues. Further, co-stressed tissues showed an increased activity of the antioxidant enzymes such as ascorbate peroxidase (APX) and glutathione reductase (GR) involved in glutathione-ascorbate cycle as well as glutathione peroxidase (GSHPx) and glutathione-S-transferase (GST) as glutathione associated enzymes when compared with Fusarium infected, Cd2+ pre-treated and untreated control tissues. In contrast, a decline in hydrogen peroxide (H2O2) and oxidised glutathione (GSSG) content was observed in co-stressed tissues as compared to Fusarium infected
tissues. Thus, a low dose (50 μM) Cd2+ pre-treatment induced both the enzymatic and non-enzymatic antioxidants to maintain redox state at cellular level. Induction of these enzymes is suggested to
be a part of defence system and play important role in offering resistance against Fusarium infection in wheat.