Biochemical and histological characterisation of Fusarium oxysporum infected wheat ( Triticum aestivum ) seedlings in vitro

In the present study response of wheat seedlings to F . oxysporum was studied which revealed that the fungus was successful in establishing infection by suppressing the antioxidative machinery of the plant as evidenced by high and rapid disease incidence. Reactive oxygen species (ROS) accumulation enhanced gradually in infected seedlings with time which was concomitant with the increase in hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) content. Biochemical changes in the activity of catalase (CAT), peroxidase (POX) and glutathione reductase (GR) was used as stress markers. Excepting for POX all the enzymes showed increased activity in the leaves as compared to the roots. Electron microscopic (SEM) analysis revealed damage to the tissue structure showing exposed epidermal layer with loosely arrange cells in infected seedlings. The results presented in this paper add to the knowledge of the events and mechanisms related to the mode of infection of F . oxysporum in wheat.