Abstract:
Medicinal plants are of great commercial and economic importance due to the
presence of special chemical constituents known as bioactive phytochemicals or
secondary metabolites (SMs). However, their increasing demand and the lack of
proper cultivation systems have resulted in increased pressure on wild populations.
Consequently, these populations now face the threats of overexploitation and habitat
loss. Additionally, various factors such as specific growth and development stages,
tissue or organ specificity, as well as stress and climate change, can adversely affect
the population of medicinal plants and the production of SMs. Elicitation is an
effective technique built on the understanding of a plant's natural defense mechanism,
utilizing various biotic and abiotic factors. In this study, two types of abiotic elicitors
were employed: biosynthesized silver nanoparticles derived from an endophytic
bacterium and salicylic acid. These elicitors were applied using the elicitation
technique on four types of hydroponically grown medicinal plants viz., Fenugreek,
Flax, Cumin, and Black Cumin. The aim was to observe the effects of elicitation on
different plant parameters, including growth and the content of primary and SMs, with
the goal of enhancing plant yield and medicinal properties. The analysis of the results
revealed a significant increase in all tested parameters at various concentrations of the
applied elicitors. The highest significant results were mostly observed at the lowest
possible concentration, such as 1 mM of AgNPs, 2 mM of SA, and a ratio of 1:2 or
2:1 of AgNPs+SA. The utilization of elicitation techniques with efficient and cost effective methodologies holds great future potential in sustainable agricultural
practices for cultivating medicinal plants. This approach can not only enhance yield
and therapeutic properties but also alleviate pressure on wild populations and aid in
the conservation of natural resources.
