The interactive effect of exogenous application of salicylic acid (SA) and sodium nitroprusside (SNP), a donor of nitric oxide, on zinc (Zn) toxicity was assessed in Zn-stressed safflower (Carthamus tinctorius L.) seedlings. | Turkish Journal of Botany Turk J Bot (2018) 42: 271-279 © TÜBİTAK doi: Research Article Effects of exogenous salicylic acid and sodium nitroprusside on α-tocopherol and phytochelatin biosynthesis in zinc-stressed safflower plants 1, 2 3 Shahram NAMDJOYAN *, Hossein KERMANIAN , Ali Abolhasani SOORKI , 4 5 Sedigheh MODARRES TABATABAEI , Nazli ELYASI 1 Department of Biology, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran 2 Department of Pulp and Paper, Faculty of Energy and New Technology, Shahid Beheshti University, Tehran, Iran 3 ACECR-Research Institute of Applied Sciences, Shahid Beheshti University, Tehran, Iran 4 Iranian Department of the Environment, Tehran, Iran 5 Department of Statistics, Trade Planning Office, Trade Promotion Organization, Tehran, Iran Received: Accepted/Published Online: Final Version: Abstract: The interactive effect of exogenous application of salicylic acid (SA) and sodium nitroprusside (SNP), a donor of nitric oxide, on zinc (Zn) toxicity was assessed in Zn-stressed safflower (Carthamus tinctorius L.) seedlings. Exposure to 500 µM for 10 days caused an increment in the levels of malondialdehyde (MDA), H2O2, α-tocopherol, phytochelatins (PCs), and proline. Application of SA or SNP, and especially their combination, resulted in remarkable decrease in MDA, H2O2, and proline content while chlorophyll content and the activity of catalase, ascorbate peroxidase, and guaiacol peroxidase exhibited a significant induction in comparison with plants subjected to Zn treatment alone. In Zn-treated plants, addition of SA and SA + SNP caused a progressive increase in α-tocopherol levels in comparison with plants treated with Zn alone. In plants subjected to Zn excess, no significant association was found between PC levels and the supplementation of SA, while application of SNP and SA + SNP caused a significant increase in PC .
