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.

Farkas, E., Kursinszki, L., Szőke, É. & Molnár, K. 2015. New chemotypes of the lichens Xanthoparmelia pulvinaris and X. subdiffluens (Parmeliaceae, Ascomycota). — Herzogia 28: 679–689. New chemotypes of Xanthoparmelia pulvinaris and X. subdiffluens containing norstictic acid were identified among many of the Hungarian collections of these species using HPTLC and confirmed by LC-MS. The two species are characterised, the possible functional role of norstictic acid is briefly discussed and the importance of protecting populations with norstictic acid in nature is emphasized. Zusammenfassung: Farkas, E., Kursinszki, L., Szőke, É. & Molnár, K. 2015. Neue Chemotypen bei den Flechtenarten Xanthoparmelia pulvinaris und X. subdiffluens (Parmeliaceae, Ascomycota). — Herzogia 28: 679–689. Neue Chemotypen der Arten Xanthoparmelia pulvinaris und X. subdiffluens mit Norstictinsäure wurden in vielen ungarischen Aufsammlungen dieser Arten mit HPTLC festgestellt und mit LC-MS bestätigt. Die zwei Arten werden kurz charakterisiert, die mögliche funktionelle Bedeutung von Norstictinsäure wird kurz diskutiert, und die Notwendigkeit, diese Populationen mit Norstictinsäure im Naturschutz zu berücksichtigen, wird unterstrichen.

Seeds of industrial hemp have high nutritional and healthcare value, which can be further improved by proper cultivation methods. Biochemical properties of hemp seeds that are beneficial for human use can be modulated through variation of the molar ratio between the inorganic nitrogen and phosphorus supplied with the nutrient medium, as well as by creating a moderate water deficit during controlled irrigation. The aim of this study was to investigate the influence of two N:P ratios (i.e. 8 mM nitrogen as nitrate to 2 mM phosphorus as phosphate, and 3 mM nitrogen to 6 mM phosphorus), combined with two water supply regimes (sufficient and insufficient) on vegetative growth parameters, seed production, seed oil, protein, vitamin E, iron, zinc and manganese content of two industrial hemp cultivars (‘Jubileu’ and ‘Zenit’). The experiments were performed in a greenhouse, under controlled conditions. Even if plants receiving a lower N:P ratio and lower water supply had a decreased growth index and the shoot fresh weight was smaller, no statistically significant difference could be registered in the seed production of the different experimental variants. The oil content of seeds could be increased by a lower N:P ratio and by water deficit, while seed protein content was higher upon a higher N:P ratio and upon water shortage, for both cultivars. The highest vitamin E content of hemp seed oil was found when plants were subjected to the combined influence of lowered N:P ratio and water insufficiency. The iron content of seeds showed no changes between the different experimental variants. In seeds of the ‘Jubileu’ variety the zinc content was increased by water shortage when the N:P ratio was lower, while the highest manganese content was measured when plants received sufficient water and lowered N:P ratio. As for the ‘Zenit’ variety, the highest zinc and manganese content of seeds was obtained when plants received through the nutrient solution 8 mM nitrate and 2 mM phosphate (i.e. the N:P ratio was 4:1). The findings may contribute to optimization of hemp cultivation, in a cost-effective and environmental-friendly approach, for the purpose of production of higher quality seeds for human and animal consumption, as well as for the cosmetic industry.