Role of sulphate (SO42-) in improvement the growth of rocket plants (Eruca sativa L.) under selenate (SeO42-) levels

Abstract

Selenium is an essential microelement for plant growth and productivity, but high selenium levels impose toxicity in plants. A pot experiment was conducted to investigate the role of sulphate concentrations for ameliorate the adverse effects of high selenate levels on growth of 30-day old rocket plants (cv Egyptian baladi). High Se levels preferentially decreased the biomasses, succulent values in leaves and roots as well as leaf area of rocket plants. This was associated with a suppression of photosynthetic pigments and foliar nutrient elements (K, P, S, Mg and N as NO 3 -) with an increase of Se content. Supplementation the high Se-containing medium with double SO 4 2-concentration in 1/10 Hoagland solution markedly antagonized Se uptake and its assimilation reflecting the shift-off to some extent-the inhibitory effect of high Se on growth through induction of minerals uptake and biosynthesis of photosynthetic pigments. In addition; changing the protein profile revealed variations in protein patterns and a decrease in selenoprotein biosynthesis by increasing sulphate concentration. However, supplementation of plants with low selenate (2 ppm) level combined with high sulphate (2 ppm) concentration resulted in an optimal growth.