The growing demand for native planting material in ecological restoration and rehabilitation for agro-silvo-pastoral ecosystems has resulted in a major global industry in their sourcing, multiplication, and sale. Plant tissue culture is used for producing high-quality, disease-free, and true-to-type plants at a fast rate. Micropropagation can help to meet the increasing demand for planting material and afforestation programs. However, in vitro plant propagation is an expensive technique compared to conventional methods using suckers, seeds, and cuttings. Therefore, adopting measures to lower production costs without compromising plant quality is essential. This can be achieved by improving the culture media composition. Incorporating organic growth additives can stimulate tissue growth and increase the number of shoots, leaves, and roots in culture media. Organic growth supplementation speeds up the formation and development of cultures and yields vigorous plants. Plant regeneration from meristems (shoot tips and axillary buds) is a reliable way to produce true-to-type plants compared with callus and somatic embryogenesis regeneration, but in vitro culture environments can be mutagenic. Therefore, detecting somaclonal variations at an early stage of development is considered crucial in propagating plants. The genetic stability of in vitro regenerated plants needs to be ascertained by using DNA-based molecular markers. This review aims to provide up-to-date research progress on incorporating organic growth additives to enhance in vitro tissue culture protocols and to emphasize the importance of using PCR-based molecular markers such as RAPD, ISSR, SSR, and SCoT. The review was assessed based on the peer-reviewed works published in scientific databases including Science Direct, Scopus, Springer, JSTOR, onlinelibrary, and Google Scholar.

Essential oils (EOs) from combined plant materials offer a promising alternative to conventional extraction by enhancing chemical diversity and bioactivity. This study evaluated the chemical composition and insecticidal properties of individual and combined plant EOs from Cymbopogon citratus, Eucalyptus camaldulensis, Eucalyptus lehmannii, Salvia rosmarinus and Thymus vulgaris were evaluated against aphids. Binary and ternary combinations were prepared in equal proportions prior to hydrodistillation. GC-MS analysis revealed significant compositional shifts in EOs from combined plant materials. Major compounds in individual oils included citral (53.11%) and neral (29.14%) in C. citratus, thymol (70.84%) in T. vulgaris, and eucalyptol as the predominant compound in E. camaldulensis (66.51%), E. lehmannii (56.99%) and S. rosmarinus (46.56%), respectively. In the combined oils, the relative abundance of these constituents was altered, and in some cases new constituents were introduced. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) revealed that combined plant EOs clustered near their parental oils, indicating compositional inheritance. Contact toxicity assay against Aphis fabae demonstrated enhanced efficacy of the combined oils, with reduced LC₅₀ values (1.39 µL mL⁻¹ for E. camaldulensis + T. vulgaris) and synergistic interactions, indicated by a co-toxicity coefficient (CTC) of 221.58 and elevated synergistic factors. Pearson correlation analysis and Partial Least Squares (PLS) regression jointly identified Acorenone B and thymol as negatively, and caryophyllene as positively correlated compounds, all with relatively high contribution to insecticidal activity, ranking highest with a Variable Importance in Projection (VIP) scores > 1.0. While PLS model had modest predictive power, the integration of these statistical approaches supports the insecticidal potential of combined plant-derived EOS in laboratory bioassays and indicates their relevance to sustainable crop protection.

Excessive reliance on synthetic agrochemicals has raised environmental and health concerns. Consequently, there is a growing interest in exploring natural alternatives such as plant-derived essential oils for pest and disease management. This study eval-uated the essential oils extracted from Lavandula dentata, Salvia rosmarinus, and Thymus vulgaris (Lamiaceae), as well as seven Eucalyptus species (Myrtaceae). Lavandula dentata produced the highest essential oil yield (3.6%), followed by Thymus vulgaris (2.7%) and Salvia rosmarinus (0.66%). In the Myrtaceae family, the yields ranged from 0.18% to 1.94%. Chemical analysis via GC-MS and GC-FID revealed a high content of oxygenat-ed monoterpenes, with concentrations ranging from 39.95% to 88.31%. The main con-stituents were 1.8 cineole, α-pinene, β-pinene, p-cymene and camphor except for Thy-mus vulgaris EO, where thymol (72.37%) was the dominant component. Essential oils exhibited significant antifungal activity against six phytopathogenic strains. Thymus vulgaris, even at low concentrations, demonstrated fungicidal activity against all the strains. Additionally, Thymus vulgaris essential oil showed the highest antioxidant po-tential, surpassing the common standard, Trolox. The present findings highlight the potential of essential oils as natural fungicides, offering an alternative to conventional synthetic fungicides. This research supports the potential use of plant-derived oils in multifunctional landscapes and integrated pest management strategies.

Essential oils (EOs) obtained from combined plant materials offer a promising alternative to conventional extraction by enhancing chemical diversity and bioactivity through synergistic interactions. Given the growing interest in insecticidal EOs activity and use in agriculture, the chemical composition and insecticidal properties of individual and combined plant EOs from Cymbopogon citratus, Eucalyptus camaldulensis, Eucalyptus lehmannii, Salvia rosmarinus and Thymus vulgaris were evaluated against aphids. Plant materials were mixed in equal proportions prior to hydrodistillation to produce binary and ternary combinations. GC-MS analysis revealed significant compositional shifts in EOs from combined plant materials. Major compounds in individual oils included citral (53.11%) and neral (29.14%) in C. citratus, thymol (70.84%) in T. vulgaris, and eucalyptol as the predominant compound in E. camaldulensis (66.51%), E. lehmannii (56.99%) and S. rosmarinus (46.56%), respectively. In the combined oils, the relative abundance of these constituents was altered, and new minor constituents were introduced. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) revealed that combined plant EOs clustered close to their parental oils, indicating compositional inheritance rather than entirely novel profiles. Insecticidal assays conducted against Aphis fabae demonstrated enhanced efficacy of the combined oils, as evidenced by reduced LC₅₀ values (1.39 µL mL-1 for E. camaldulensis + T. vulgaris) and pronounced synergistic interactions, indicated by a co-toxicity coefficient (CTC) of 221.58) and elevated synergistic factors. Pearson correlation analysis and Partial Least Squares (PLS) regression jointly identified Acorenone B, thymol and caryophyllene as principal contributors to insecticidal activity, each exhibiting distinct correlation directions. These three compounds ranked highest among the 18 compounds with a Variable Importance in Projection (VIP) scores exceeding 1.0. The integration of these statistical approaches substantiates the insecticidal potential of combined plant-derived EOS and underscores their relevance in advancing sustainable crop protection strategies.