Study of sodium nitroprusside spraying on the agronomic and physiological traits of safflower (Carthamus tinctorius L.) in arsenic contaminated soils.

In order to investigate the effect of sodium nitroprusside levels on growth and quantitative and qualitative characteristics of safflower (Carthamus tinctorius L.) in arsenic contaminated soils, a pot experiment was conducted in a research greenhouse of Faculty of Agriculture, Islamic Azad University, Varamin-Pishva Branch, in 2016-2017 in factorial experiment and in the form of design Completely randomized in 3 replications. The experimental treatments included of sodium nitroprusside spraying at three levels: (0, 50 and 100 μm) and soil contamination with arsenic at four levels (0, 30, 60 and 90 mg of arsenic per kg of soil). The results showed that arsenic and sodium nitroprusside had a significant effect on grain yield, 1000 grain weight, catalase enzyme, malondialdehyde content, proline content and safflower arsenic content. The highest grain yield was obtained in sodium nitroprusside treatments in application of 100 μM (with an average of 1.01 g / plant), and the lowest was related to control treatment (no application) with mean of 0.83 g / plant. By increasing the concentration of arsenic, yield and yield components decreased, and the plant increased its proline content to cope with stress. Application of sodium nitroproside reduced stress in plants under arsenic toxicity. No significant differences were observed between the concentrations of sodium nitroprusside spraying. With increasing arsenic levels, the amount of arsenic content increased and sodium nitroprusside reduced the amount of arsenic in the seed. In general, use of sodium nitroprusside as a regulator in the metabolism of free oxygen radicals reduces the effects of oxidative stress caused by soil contamination with arsenic.