Mass propagation of medicinal plants in hydroponic condition, especially in salt soils have a special importance. The experiment was conducted as a factorial and in a completely randomized block design Hydroponically grown O. basilicum L. plants were exposed to 4 levels (0, 25, 50 and 100 mg/l) of Multiwalled carbon nanotubes treatment and 3 levels (0, 50 and 100 mM NaCl) of salt stress. Plants daily irrigated with quarter-strength Hoagland solution and Harvested inflorescences and leaves of each sample were air dried at room temperature. The hydro-distilled oils were analyzed by GC/MS. Fifty components were identified in the inflorescence and leaf essential oils of the basil plants. Salinity and MWCNTs treatment in low to moderate concentration increased the essential oil percentage. Results demonstrated the major pathway of the essential oil was Phenylpropanoids pathway that main constituents was estragole and in shikimic acid pathway the main constituents linalool was identified that were (60/48 % and 10/18%), respectively. -cadinol, Caryophyllene, and Germacrene D were the other the most constituents that (4/26%, 4/92 and 6/56%) respectively. In total, considering the previous reports, it seems that the essential oil composition of hydroponically grown O. basilicum L. had volatile constituents probably with potential applicability in the pharmaceutical and food industries.
