The Response of Hypericum Perfpratum L. to the Application of Selenium and Nano-selenium
Abstract Background: In terms of medicinal and therapeutic properties, H. perforatum is the important species. However, Selenium has been applied as an alleviation strategy subjected to producing essential oils and biomass.Method: For this study, a randomized complete block design with three replications was used so that each experimental unit comprised of 30 number 8 pots. The treatments included the foliar application of selenium (6, 8, 10, and 12 mg/l), nano-selenium (6, 8, 10, and 12 mg/l), and control (distilled water), applied at the rosette stage and harvesting at 50% flowering stage.Results: The results of the analysis of variance showed that the effect of selenium and nano selenium fertilizers was significant (p<0.01) on plant height, inflorescence length, number of inflorescences, inflorescence weight, shoot weight, root length, the total weight of biomass, essential oil percentage, the content of hypericin and hyperforin, the selenium accumulation in the plant, relative leaf water content, the content of chlorophylls a, b, and total, the content of phenol, the content of proline, production and accumulation of catalase, peroxidase, malondialdehyde, and DPPH enzymes. The highest inflorescence weight (21 g/plant), shoot weight (70 g/plant), and essential oil content (0.14%) were obtained from the control treatment. The highest accumulation of hypericin (3.8 mg/g dry matter) was obtained from the foliar application of 8 mg/l selenium. The maximum accumulation of hyperforin (57 mg/g dry matter) was obtained from the foliar application of 10 mg/l selenium. The highest accumulation of selenium (287.52 μg/g dry matter) was obtained in the foliar application of 12 mg/l nano-selenium.Conclusion: If the purpose of producing H. perforatum is to use the shoots and essential oils of the plant, then the use of selenium and nano-selenium is not recommended at all and should not be used. If the goal is to produce high hypericin, high hyperforin, and also the accumulation of selenium in the plant, the use of treatments of 6 and 8 mg/l of selenium and nano-selenium could be applied.