Biochemical and Histo-Anatomical Responses of Lavandula angustifolia Mill. to Spruce and Beech Bark Extracts Application.

This paper aims to assess the biological responses of Lavandula angustifolia Mill. to beech and spruce bark crude extract application. Thus, the biological activity of bark extracts was assessed by determining the germination capacity, biomass production, histo-anatomical aspects and photo-assimilatory pigment accumulation, and by quantitative and qualitative volatile compounds analysis. The application of spruce bark extract (500 mg dry bark/100 mL solvent) resulted in a better development of the leaf tissue and an increase in foliar biomass. We observed the stimulating effect of photo-assimilating pigments accumulation, for all experimental variants, compared to the control. Also, the amount of volatile oil was significantly higher in the treated plants with spruce bark extract (500 mg dry bark/100 mL solvent). Some volatile compounds (cyclen, borneol, cryptone, santalen, and caryophyllene oxide ß-farnesene) were identified only in the experimental variants. Also, in the experimental variants, an increase in the quantity of limonene, linalyl acetate and lavandulol was observed. These preliminary results showed that the beech and spruce bark extracts can have biological activities and influence the production of volatile oil in Lavandula angustifolia, causing significant changes in the phytochemical profile of the essential oil. Thus, forest waste bark extracts could be recommended as natural bioregulators in lavender crops.

Increase in Artemisia annua Plant Biomass Artemisinin Content and Guaiacol Peroxidase Activity Using the Arbuscular Mycorrhizal Fungus Rhizophagus irregularis.

The main objective of this study was to investigate Artemisia annua plant property variations in terms of plant biomass, glandular trichome numbers, artemisinin production and Guaiacol peroxidase (GPOX) activity when plants are in mutualism with AMF. According to the results, A. annua mutualism with AMF significantly increased the most important and pharmaceutically relevant factors of fresh and dry plant biomass. This increase, especially in the biomass of plant herba (leaves), was 30% higher during the vegetation period and remained high (29% higher than for control) when plants were harvested at the end of the vegetation period. Similar differences in dry biomass were also detected. Glandular trichomas numbers increased by 40%, and the artemisinin content by 17% under AMF colonization. No effects due to AMF on chlorophyll variations were detected, while GPOX enzyme concentrations increased significantly under AMF colonization. Altogether the Artemisia plant properties with high pharmaceutically importance (fresh and dry biomass of leaves and artemisinin, number of trichomes and the artemisinin content) were significantly improved by AMF, the application in Artemisia cultivation can be an effective and cheap method. The high GPOX activity under AMF colonization indicate an enhanced oxidative stress alleviation, therefore a higher resistance to water deficiency, mechanisms important under climate conditions with low water supply where Artemisia is usually cultivated.