Artemisinin extracted from Artemisia annua has been used efficiently in malaria treatment since 2005. In this study, the variations in plant parameters (plant biomass, glandular trichome density, essential oil total chemical content, artemisinin production, and polyphenol oxidase (PPO) activity) were tested under different soil types (Luvisol, Gleysol, Anthrosol and sterile peat) and cultivation conditions (potted plants in semi-open field, and open field experiments) for plants inoculated with arbuscular mycorrhizal fungus (AMF) Rizophagus irregularis. Under semi-open field conditions, the AMF colonization of A. annua plant roots varied, and presented the highest percentage in Luvisol and sterile peat. The increase in the root colonization rate positively influenced some plant parameters (biomass, glandular trichome density, artemisinin concentration, essential oil quantity and composition), but no effects on PPO enzyme activity were detected. AMF fungus R. irregularis significantly increased the artemisinin content and essential oil yield of plants cultivated in Luvisol, Gleysol, Anthrosol and in peat. These soil types can offer appropriate conditions for A. annua cultivation and artemisinin production even on a smaller scale. Under open field conditions, low (about 5%) AMF colonization was observed. No differences in artemisin contents were detected, but essential oil yield significantly increased compared to control plants. AMF treatment increased beta-farnesene and germacrene D concentrations in Artemisia plants in the open field experiment.

The cultivation of Echinacea purpurea for commerce and obtaining high-quality plant material on a large scale remain a challenge for growers. Another challenge for the following decades is to create sustainable agriculture that meets society’s needs, has no environmental impact, and reduces the use of fertilizers and pesticides. The aims of this overview were: (1) to present the importance of the chemical compounds reported in E. purpurea; (1) to synthesize results about cultivation of the E. purpurea with arbuscular mycorrhizal fungi (AMF) and associated microorganisms; (2) to exemplify similar research with plants from the Asteraceae family, due to the limited number of published Echinacea studies; (3) to collect recent findings about how the inoculation with AMF affects gene expressions in the host plants; (4) to propose perspective research directions in the cultivation of E. purpurea, in order to increase biomass and economic importance of secondary metabolite production in plants. The AMF inocula used in the Echinacea experiments was mainly Rhizophagus irregularis. The studies found in the selected period (2012–2022), reported the effects of 21 AMFs used as single inocula or as a mixture on growth and secondary metabolites of 17 plant taxa from the Asteraceae family. Secondary metabolite production and growth of the economic plants were affected by mutualistic, symbiotic or parasitic microorganisms via upregulation of the genes involved in hormonal synthesis, glandular hair formation, and in the mevalonate (MVA), methyl erythritol phosphate (MEP) and phenylpropanoid pathways. However, these studies have mostly been carried out under controlled conditions, in greenhouses or in vitro in sterile environments. Since the effect of AMF depends on the variety of field conditions, more research on the application of different AMF (single and in various combinations with bacteria) to plants growing in the field would be necessary. For the identification of the most effective synergistic combinations of AMF and related bacterial populations, transcriptomic and metabolomic investigations might also be useful.

Studies conducted in controlled environments showed that seed priming and foliar treatments with various bioactive substances can stimulate germination, uniform seedling emergence, photosynthesis, and nutrient uptake efficiency and can lead to increased productivity, crop stand, and quality. Only a few studies provide a comparative experimental outlook about the use of the bioactive substances in open-field cultivated canola. The aim of this study was to investigate the effects of seed priming and foliar treatment with ascorbate (AsA), cysteine (Cys), and triacontanol (Tria) on the growth and yield parameters of two canola cultivars rapeseed cultivars (“Factor” and “Hybrirock”) under open-field conditions for three growing seasons under temperate conditions from Central Transylvania. Plant growth and yield parameters were recorded at different plant development stages: in autumn (early vegetative period), in spring, and at harvest. Not all substances that have undergone laboratory testing were successful in the field. Seed priming with 10 ppm Cys and AsA had beneficial effects on the development of seedlings, whereas their foliar application enhanced the number of silique, seed yield, and the oil content of the studied canola cultivars. The effects of Tria were visible on the biometrics parameters only in autumn and spring, and also on the root parameters, but in some cases, 10 ppm Tria had no effect on plants, or even a negative effect could be observed on important parameters for agriculture such as estimated seed yield, seed yield/plant, and oil content. Optimizing treatment and application by determination of the lowest effective concentration, together with the frequency of treatments and persistence effects are crucial for cost-effectiveness.

Hercaleum sphondylium L., commonly known as hogweed, is a plant species that has been employed as an ingredient in food supplements aimed at enhancing reproductive organ functionality, restoring hormonal equilibrium, and producing an aphrodisiac effect. Importantly, the European Food Safety Authority (EFSA) has designated it as a “substance of possible concern for human health” when found in food and food supplements, as detailed in the EFSA compendium of botanicals. Given the potential health consequences associated with the ingestion of furocoumarin-containing plants, the primary objective of this study was to develop a straightforward and rapid method for screening various furocoumarins (bergapten, isobergapten, isopimpinellin, imperatorin, and xanthotoxin) that are found in hogweed plant products and hogweed-derived food supplements. A novel ultrafast micellar electrokinetic chromatographic method was established, achieving analysis durations of less than 3 min for the complete separation of the analytes. This method is additionally characterized by its simplicity, allowing for the analysis of samples following a rapid extraction procedure and dilution, without necessitating extra cleanup steps. The investigation of ten food supplements indicated that seven products contained no detectable levels of furocoumarins, one product presented levels close to the harmless threshold, and two products exhibited concentrations significantly exceeding this threshold. The results of this study illustrate the potential of micellar electrokinetic chromatography as a feasible alternative technique for the analysis of furocoumarins in herbal products and food supplements.

Recent studies have shown that vesicular-arbuscular mycorrhizae stimulate plant growth in case of Artemisia annua plants. According to these studies mycorrhization can enhance plant height and biomasses, shoot branching and inter-nodal length, foliar glandular hair density, and nutrient status of shoots and leafs. Contradictory data were obtained in case of leaf chlorophyll content and photosynthetic rate. The effects of vesicular-arbuscular mycorrhizae on roots, shoots and leafs anatomy of A. annua have not been studied yet. The aim of this paper was to compare the microscopic characteristics of the vegetative organs from the Artemisia annua plants treated with vesicular-arbuscular mycorrhizae, with those from the control plants. Rhizophagus irregularis influenced the development of vascular tissues in root and stem of Artemisia plants by increasing their surface in the organs. Mycorrhization also reduced the percentage of lignification in the cortex of the root, increased the percentage of palisade parenchyma in leaf and had a positive effect on foliar glandular hair density. Further investigations are necessary to find out the role of these histo-anatomic alterations in the growth and development of Artemisia plants.