Plants face various stresses, particularly water deficit, which negatively impacts photosynthesis, growth, and development, thereby limiting agricultural production. Utilizing growth regulators, such as amino acids and polyamines, to enhance osmotic stress tolerance is a crucial area of research in sustainable agriculture. This study investigates the impact of arginine and spermine treatments on various growth attributes, enzymatic and non-enzymatic antioxidants, photosynthetic pigments, protein and lipid peroxidation, and yield traits of fenugreek plants under both normal and drought conditions. The results indicate that drought conditions significantly reduce morphological characteristics, leaf pigments, and yield traits. However, the application of arginine and spermine enhances these parameters, with spermine showing a more pronounced effect. Additionally, treatments boost antioxidant enzymes activities and improve the levels of non-enzymatic antioxidants and osmolytes, contributing to better stress tolerance and growth performance. Principal component analysis confirms that drought significantly alters plant physiology, increasing proline and malondialdehyde levels, while arginine and spermine alleviate drought stress by enhancing antioxidant activity and osmolyte accumulation. The current investigation aims to evaluate the effectiveness of spermine and arginine treatments on various growth attributes and stress tolerance of fenugreek plants under normal and drought conditions, focusing on their comparative efficacy.

Chicory (Cichorium intybus L.) roots are valued in medicine for their potential health benefits. Producing callus from chicory roots through tissue culture technology can streamline bioactive metabolites production and ensure a sustainable supply chain. The current study explored the impact of plant growth regulators (PGRs) and light conditions on the characteristics of callus induced from C. intybus root explants. The effect of fungal elicitors [yeast extract (YE), Fusarium oxysporum, and Aspergillus niger] on bioactive metabolite production from root-derived callus was investigated. Callus color varied notably between a 16/8 h light/dark cycle and complete dark, with differences in texture based on PGR concentrations and light conditions. High weights of callus formed were generally recorded under the 16/8 h light/dark cycle. Low concentrations of YE (1 g/L) and F. oxysporum (0.25 g/L) enhanced callus biomass fresh weight, while high concentrations of A. niger (1 g/L) improved callus dry matter significantly. The content and productivity of total phenolic were maximized at 1 g/L of YE and 1 g/L of F. oxysporum. Callus cultures elicited with a higher level of A. niger recorded the higher values of total flavonoid production. High-performance liquid chromatography (HPLC) analysis revealed significant variations in chlorogenic acid, catechin, and caffeic acid levels among the different elicited cultures. A. niger at 1 g/L notably increased chlorogenic acid content, while catechin levels were enhanced by specific concentrations of YE. Catalase (CAT) activity was significantly affected by different elicitors, while only the higher level of F. oxysporum and A. niger showed a significant increase in peroxidase (POD) activity. DPPH scavenging activity was elevated by all fungal elicitors. Principal Component Analysis delineated distinct variations in callus traits in response to different elicitors, with specific treatments showcasing enhanced biomass production, bioactive compound accumulation, and antioxidant activities. Through meticulous experimentation, this study paves the way for enhancing chicory root-derived products, ensuring sustainable production and potent bioactivity.