Nanoparticles in appropriate dose can used as an eco-friendly abiotic elicitor to induce specific and novel secondary metabolites with high performance. The present study was conducted to investigate the silver nanoparticles (Ag-NPs) at 0, 200, 400, and 600 ppm on morpho-physiological, yield, and phytochemical parameters of feverfew (Tanacetum parthenium L.). The essential oil was obtained by hydro-distillation and analyzed by using GC-FID and GC/MS. The HPLC was used to quantifying the parthenolide content. The results showed that the effect of Ag-NPs application on studied traits were in dose depended manner. The Ag-NPs treatment at 200 ppm increased the fresh weight, biological yield, dry weight, and flower yield up to 29.12 %, 31.61 %, 28.71 %, and 44.93 % respectively. However, the growth of treated plants with higher concentrations of Ag-NPs (400 and 600 ppm) was decreased compared with untreated plants. All Ag-NPs treatments caused a significant increment of the chlorophyll index, parthenolide content (as a valuable anticancer compound) and essential oil content. The highest content of chlorophyll index (49.90), parthenolide content (0.96 mg g−1 DW) and essential oil content (0.84 %) was measured in spayed plants with 600 ppm Ag-NPs. Also, the Ag-NPs application considerably affected the essential oil quality. With increasing the Ag-NPs concentration the oxygenated monoterpenes represented by camphor and trans-chrysanthenyl acetate were increased so that the highest content of camphor (45.13 %) and trans-chrysanthenyl acetate (32.04 %) was obtained at 600 ppm. Generally, it can be concluded that Ag-NPs could act as an elicitor to induce the more production of favorable secondary metabolites.
