Changes morpho-physiological responses of lemon verbena to different concentrations of single-walled and multi-walled carbon nanotubes

Lemon verbena (Lippia citriodora) is a valuable medicinal plant widely utilized in the food, pharmaceutical, and cosmetic industries due to its rich content of secondary metabolites, including phenolics, flavonoids, and aromatic essential oils. In recent years, the application of carbon nanotubes (CNTs) has emerged as a novel approach to enhancing plant growth and improving the production of bioactive compounds. This study evaluated the effects of different concentrations of single-walled and multi-walled carbon nanotubes (۰, ۰.۲۵, ۰.۵, ۱, and ۲ g) on the physiological and morphological responses of lemon verbena under greenhouse conditions. The experiment was conducted using a completely randomized design with three replications, and CNT treatments were applied as foliar sprays. The results showed that the traits were influenced by the simple effects of carbon nanotube concentrations. Treating with ۲ g of carbon nanotubes significantly increased proline (by ۷۰%), phenols (by ۱۹%), and total chlorophyll (by ۵۸%) compared to the control. As the concentration of carbon nanotubes increased, along with a decrease in malondialdehyde levels, a rising trend was observed in enzyme activities, with the highest activities recorded in the ۲ g treatment: superoxide dismutase (۲.۰۶۷ μmol g-۱ FW), peroxidase (۱.۱۵ μmol g-۱ FW), ascorbate peroxidase (۲۷.۰۸ μmol g-۱ FW), and catalase (۳.۵۷ μmol g-۱ FW). Additionally, growth indices such as dry weight of both aerial and underground parts were positively affected by higher concentrations of nanotubes. The highest essential oil percentage was observed in the ۲ g treatment (۱.۰۱۷%). Overall, the use of single-walled carbon nanotubes at a concentration of ۲ g, due to its economic efficiency, can be considered an effective tool for improving growth and essential oil content in lemon verbena plants.

کلیدواژه ها:

Allicitor ، Carbon nanotubes ، Medicinal Plant ، Secondary metabolites ، الیسیتور ، گیاهان دارویی ، متابولیت های ثانویه ، نانوتیوب کربنی