Enhancement of Antioxidant Enzymes Activities, Drought Stress Tolerances and Quality of Potato Plants as Response to Algal Foliar Application.

Background: Different types of environmental stress may induce several physiological, biochemical and molecular responses in several crop plants. According to a patent study, several types of low antioxidant defense compounds and the activity of various antioxidant defense enzymes are induced in plants grown under various biotic and abiotic stress factors.

Methods: In this work, the responses of potatoes plant treated with algae extract to drought stress were examined by evaluating the crop yield of tuber, cellular biological compounds (total carbohydrates and proteins), mineral composition and enzyme and non-enzyme antioxidant systems and total oxidative compounds.

Results: The yield of tuber, concentration of low antioxidant defense compounds (glutathione, ascorbate, carotenoids, total phenol, flavonoids and tocopherols) and the activity of various antioxidant defense enzymes (catalase CAT; peroxidase POD; ascorbate peroxidase APX and superoxide dismutase SOD) in tuber of treated potato plants with algae extract were significantly increased compared with that in non-treated plants. In addition, essential elements: Fe, K, Ca, Mg and P were accumulated at high concentration in treated plant than that in untreated plants. The screening of antioxidant activity of the ethanolic extract of tubers potatoes treated with algae extracts using the di-(phenyl)-(2,4,6- trinitrophenyl) iminoazanium radical (DPPH) assay radical-scavenging showed an appreciable reduction of the stable radical DPPH with an IC50 of 75 µg/ml.

Conclusion: The results suggest that the algae foliar extracts application can improve non-enzymatic and enzymatic antioxidant defense systems in potatoes plant cultivated under drought stress conditions, and it may be recommended for application in arid and semiarid regions.