Jornal de Fisiologia e Patologia Vegetal

Ascorbic Acid Reduces the Phytotoxic Effects of Selenium on Rice (Oryza Sativa L.) by Up-Regulation of Antioxidative and Metal-Tolerance Mechanisms

Shuchi Sharma, Navneet Kaur, Simranjeet Kaur and Harsh Nayyar

Ascorbic Acid Reduces the Phytotoxic Effects of Selenium on Rice (Oryza Sativa L.) by Up-Regulation of Antioxidative and Metal-Tolerance Mechanisms

Selenium (Se) in trace concentrations (<1mg/kg) is proved to be beneficial for many plant species, but is considered toxic at higher concentrations and adversely affects the potential growth and yield of plants. Hence, measures are needed to minimise the phyto-toxicity of Se on plants. Ascorbic acid (Asc) has vital roles as a redox buffer, a strong antioxidant, regulator of enzymes of photosynthesis, phytohormones, cell division and growth in plants. In the present study, rice, which is a sensitive to Se-stress, was grown under controlled laboratory conditions (30/25; 15/9h, light/ dark; light intensity: 350 umol m-2 s-1, RH: 65-70%) with selenium (as sodium selenate; 1, 2.5 and 5 ppm) in the absence or presence of 50 μM Asc for ten days in half-strength Hoagland solution. Se at 2.5 ppm concentration resulted in 22.6 and 30% inhibition of roots and shoots, respectively, which increased markedly at 5.0 ppm (47% for roots 60% for shoots).