Modulation of salt (NaCl)-induced effects on oil composition and fatty acid profile of sunflower (Helianthus annuus L.) by exogenous application of salicylic acid

BACKGROUND: Salicylic acid (SA) is a potential endogenous plant hormone that plays an important role in plant growth and development. Since sunflower yield and its seed oil yield are adversely affected by salinity, in this study the role of SA in modulating salt (NaCl)-induced effects on various yield and oil characteristics of sunflower was investigated. For this purpose a greenhouse experiment comprising two sunflower hybrid lines (Hysun-33 and SF-187), two NaCl levels (0 and 120 mmol L-1) and four SA levels (0, 100, 200 and 300 mg L-1) was conducted. RESULTS: Salt stress markedly reduced yield, oil content, linoleic acid and delta-tocopherol in both sunflower lines, while it increased linolenic acid, palmitic acid, stearic acid and alpha- and gamma-tocopherols. However, increasing levels of foliar-applied SA resulted in improved achene yield and hundred-achene weight in both lines. Foliar-applied SA caused a significant decrease in oil stearic acid and alpha- and gamma-tocopherols in both lines under non-saline and saline conditions. CONCLUSION: Salt-induced harmful effects on achene yield and oil characteristics of sunflower could be alleviated by exogenous application of SA. High doses of SA caused a marked increase in sunflower achene oil content as well as some key fatty acids. (C) 2010 Society of Chemical Industry