ORIGINAL ARTICLE

Effects of Foliar Application of ZnO Nanoparticles on Secondary Metabolite and Micro-elements of Camelina (Camelina sativa L.) Under Salinity Stress 

The present study investigated the biochemical impact of ZnO nanoparticles (NPs) and salinity stress in Camelina (Camelina sativa L.) plants. ZnO NPs were applied at 0, 20, 40 and 80 mgL-1 and salinity stress (NaCl) were at 0, 50, and 100 mM. Salinity stress significantly enhanced total phenolic compounds, anthocyanin, carotenoid and ability to scavenge the DPPH radical in shoots and roots. We demonstrate that the ZnO NPs, plant carotenoid content is profoundly affected by salinity and ZnO NPs. Salinity stress decreased zinc concentration in shoots and root, but increased macro-element such as calcium (Ca) and phosphorous (P). Application of 20 mgL^-1 ZnO NPs gave the most impact contents of calcium (Ca), phosphorous (P). With increasing ZnO NPs concentration, zinc (Zn) content was increased. Foliar application of ZnO NPs did not show any significant effect on flavonoid content in Camelina but caused increases in DPPH radical scavenging capacity in shoot and root. We found that the amount of phenolic compounds in shoot was decreased at 20 mgL^-1 of ZnO NPs concentration. ZnO NPs at 20 mgL^-1 was more provocative to reduce the effects of NaCl. Therefore, the results suggest that the appropriate concentration of ZnO NPs (20 mgL^-1) could overcome the negative effects of salt stress in Camelina.