Impact of glutathione on enhancing sunflower growth and biochemical aspects and yield to alleviate salinity stress

Abstract

The effect of presoaking sunflower seeds with various concentrations of glutathione under salt stress on growth, some biochemical aspects and yield attributes were evaluated. A greenhouse pot experiment was carried out through two consecutive successive seasons. Irrigation sunflower plants with various concentrations (0, 3000 and 6000 mg L −1 ) of saline water caused gradual decreases in growth indices, photosynthetic pigments as chlorophyll (a, b) and carotenoids, some minerals (nitrogen, phosphorus, potassium and magnesium). Yield attributes, oil% and protein % of the yielded seeds of sunflower plant were decreased significantly by different salinity levels. While, free amino acids, proline, total soluble sugars, hydrogen peroxide and lipid peroxidation were increased under salinity conditions. Moreover salinity stress increased some antioxidant enzymes and sodium contents. Soaking of seeds with the various concentrations of glutathione (20, 40 and 60 mg L −1 ) could alleviate the harmful effects of salinity stress via increasing growth indices, photosynthetic pigments, osmolytes (free amino acid, proline and total soluble sugars), the studied antioxidant enzymes and minerals contents as well as, yield attributes quantity and quality of sunflower plant. Meanwhile decreased significantly hydrogen peroxide, lipid peroxidation and sodium element of sunflower plant grown under salinity stress. In conclusion, soaking sunflower seeds in different concentrations of glutathione improve growth indices and different biochemical aspects and yield quantity and quality not only under normal irrigation water but also under different salinity levels. Glutathione exogenous treatment with 40 mg L −1 was the most effective treatment enhancing the above mentioned characters. • Salinity stress results in reduction in plant growth and biochemical alterations. • Glutathione (GSH) mitigate the adverse effect of salinity stress on growth and oxidative stress. • The effective dose of GSH application to enhance the plant stress tolerance. • The differences in fatty acid compositions of sunflower oil under treatments. • Rising the efficiency of plant yield quantity and quality.