INFLUENCE OF He-Ne LASER IRRADIATION ON PROTECTIVE ENZYME ACTIVITIES AND LIPID PEROXIDATION IN WHEAT SEEDLINGS BY DROUGHT STRESS DAMAGE

Aims We studied protective enzyme activities and lipid peroxidation in wheat seedlings treated with different concentration of PEG6000 to determine the effects of He-Ne laser on wheat (Triticum aestivum) exposed to drought stress. Methods We treated 12-day-old, drought-stressed seedlings with 5%, 10% and 15% PEG6000 for 3, 6, 9, 12 and 15 days. After 3, 6, 9, 12 and 15 days of drought stress, a He-Ne laser was employed to irradiate seedlings of spring wheat for 0, 1 and 3 min. Leaves were sampled for various analyses. Important findings He-Ne laser irradiation significantly decreased malondialdehyde (MDA) content and superoxide radical (O₂^–.)production rate and notably increased peroxidase (POD) enzyme activity and ascorbate (AsA) and glutathione (GSH) concentration in wheat seedlings exposed to moderate drought stress. We concluded that 3 min laser irradiation enhanced anti-drought characteristics of wheat seedlings treated with 5% or 10% PEG6000.