The Impact of Short-Wave UV Radiation on Peroxidase Activity in Soft Wheat Seeds

Abstract

The effect of UV radiation on plants provokes oxidative stress, accompanied by the production of reactive oxygen species that can have a direct destructive effect on cellular structures and initiate free radical oxidation of proteins, lipids, and nucleic acids. There is an antioxidant defense system in plant cells that includes a complex of low and high molecular weight compounds. Antioxidants with high molecular weight are enzymes, the key of which is peroxidase [PO]. The paper studies changes in PO activity in soft spring wheat seedlings due to grain treatment with small and medium doses of short-wave UV radiation. A UV-dosed irradiation system (Bio-Link Vilber) with the exposure time 0-60 minutes in increments of 10 minutes was used for seed treatment. Pre-soaked wheat seeds were germinated in Petri dishes. PO activity was determined colorimetrically in three-day-old wheat seedlings, according to A. L. Boyarkin [3]. When the source was irradiated for up to 30 minutes, a clear dependence of the PO activity on the exposure time was not established. The maximum increase in peroxidase activity (by 25.9% relative to the control) was detected with 30-minute UV irradiation. A further increase in exposure time led to a significant decrease in enzyme activity. Moreover, vital feedback was revealed between the activity and exposure time in the range of 30-60 minutes.