Cannabinoid accumulation in hemp depends on ROS generation and interlinked with morpho-physiological acclimation and plasticity under indoor LED environment.

Manipulation of growth and development of cannabis (Cannabis sativa L.) has received considerable interest by the scientific community due to its high value in medicinal and recreational use worldwide. This study was conducted to investigate the effects of LED spectral changes on reactive oxygen species (ROS) and cannabinoid accumulation by provoking growth, pigmentation, photosynthesis, and secondary metabolites production of cannabis grown in an indoor environment. After three weeks of vegetative growth under greenhouse condition, plants were further grown for 90 days in a plant factory treated with 4 LED light compositions with a canopy-level photosynthetic photon flux density (PPFD) of 300 µmol m-2 s-1 for 16 h. Photosynthetic pigments and photosynthetic rate were linearly increased up to 60 days and then sharply decreased which was found most prominent in L3: MB 240 (Red 85% + Blue 15%) and L4: PF 240 (Red 70% + Blue 30%) LED light compositions. A high concentration of H2O2 was also observed in L3 and L4 treatments which provoked lipid peroxidation in later growth stage. In addition, higher accumulation of cannabinoid was observed under L4 treatment in most cases. It is also evident that higher ROS created a cellular stress in plant as indicated by higher osmolyte synthesis and enzyme activity which initiate quick maturation along with higher cannabinoids accumulation in cannabis plant. Therefore, it can be concluded that ROS metabolism has a crucial role in morpho-physiological acclimation and cannabinoid accumulation in hemp plants. The findings of this study provide further insight on the use of LED light to maximize the production of cannabinoid.

Exogenous Putrescine Enhances Salt Tolerance and Ginsenosides Content in Korean Ginseng (Panax ginseng Meyer) Sprouts.

The effect of exogenously applied putrescine (Put) on salt stress tolerance was investigated in Panax ginseng. Thirty-day-old ginseng sprouts were grown in salinized nutrient solution (150 mM NaCl) for five days, while the control sprouts were grown in nutrients solution. Putrescine (0.3, 0.6, and 0.9 mM) was sprayed on the plants once at the onset of salinity treatment, whereas control plants were sprayed with water only. Ginseng seedlings tested under salinity exhibited reduced plant growth and biomass production, which was directly interlinked with reduced chlorophyll and chlorophyll fluorescence due to higher reactive oxygen species (hydrogen peroxide; H2O2) and lipid peroxidation (malondialdehyde; MDA) production. Application of Put enhanced accumulation of proline, total soluble carbohydrate, total soluble sugar and total soluble protein. At the same time, activities of antioxidant enzymes like superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase in leaves, stems, and roots of ginseng seedlings were increased. Such modulation of physio-biochemical processes reduced the level of H2O2 and MDA, which indicates a successful adaptation of ginseng seedlings to salinity stress. Moreover, protopanaxadiol (PPD) ginsenosides enhanced by both salinity stress and exogenous Put treatment. On the other hand, protopanaxatriol (PPT) ginsenosides enhanced in roots and reduced in leaves and stems under salinity stress condition. In contrast, they enhanced by exogenous Put application in all parts of the plants for most cases, also evidenced by principal component analysis. Collectively, our findings provide an important prospect for the use of Put in modulating salinity tolerance and ginsenosides content in ginseng sprouts.

Conversion Characteristics of Some Major Cannabinoids from Hemp (Cannabis sativa L.) Raw Materials by New Rapid Simultaneous Analysis Method.

This study was carried out to develop a high-performance liquid chromatography method for short-time analysis of the main cannabinoids in the inflorescence of hemp (Cannabis sativa L.). We also performed decarboxylation of the raw material using our advanced analysis technique. In this study, the UV spectrum was considered to analyze each of the four common cannabinoids, solvents, and samples, where the uniform elution of acidic cannabinoids without peak tailing and acids was tested. Optimal results were obtained when readings were taken at a wavelength of 220 nm using water and methanol containing trifluoroacetic acid as mobile phases in a solvent gradient system. The established conditions were further validated by system suitability, linearity, precision, detection limit, and quantitation limit tests. The decarboxylation index (DT50) confirmed that Δ9-THCA decarboxylated faster than CBDA, and both maintained a linear relationship with time and temperature. In addition, the loss of cannabidiol was better prevented during the decarboxylation process in the natural state than in the extracted state.

Production of Potato (Solanum tuberosum L.) Seed Tuber under Artificial LED Light Irradiation in Plant Factory.

Plant production in a plant factory is an innovative and smart idea to grow food anytime, anywhere, regardless of the outer environment. However, potato pre-basic seed tuber (PBST) production in a plant factory is a comparatively new initiative. Therefore, the aim of this study was to optimize the artificial LED light spectrum to produce PBST in a plant factory. Two potato varieties such as Golden king (V48) and Chungang (V41) were grown in soil substrate under different combination of artificial LED light combinations (such as red+blue+far-red, red+blue+white, blue+far-red, blue+white, red+far-red, and red+white) maintaining photosynthetic photon flux density (PPFD) of 100 mol m-2s-1, temperature 23/15 °C (day/night), and relative humidity 70%. The study revealed that, overall, potato plant growth (viz.; plant height, node number, leaf number, leaf length and width, fresh and dry weight) was enhanced by the red+far red light for both potato varieties. The total seed tuber number per plant was higher in red+blue+white light for V48, and red+far-red for V41. The fresh tuber weight was the highest in the red+blue+far-red light for V48 and red+blue+white for V41. The highest accumulated photosynthetic pigment (total Chlorophyll, Chlorophyll a, b and Carotenoid) was observed in red+blue+white light for both varieties. The total carbohydrate content and total sucrose content were higher in red+blue+far red and red +far red light treatment for V48 and V41, respectively. Finally, considering all factors, it is concluded that the red+blue+white light combination is deemed to be appropriate for the potato PBST production in plant factory conditions.