Blue and red light affects morphogenesis and 20-hydroxyecdisone content of in vitro Pfaffia glomerata accessions

• Published in: Journal of photochemistry and photobiology. B, Biology Biology, 2020-01, Vol.203, p.111761-111761, Article 111761
• Main Authors: Silva, Tatiane Dulcineia, Batista, Diego Silva, Fortini, Evandro Alexandre, Castro, Kamila Motta de, Felipe, Sérgio Heitor Sousa, Fernandes, Amanda Mendes, Sousa, Raysa Mayara de Jesus, Chagas, Kristhiano, Silva, José Victor Siqueira da, Correia, Ludmila Nayara de Freitas, Farias, Letícia Monteiro, Leite, João Paulo Viana, Rocha, Diego Ismael, Otoni, Wagner Campos
• Format: Article
• Language: English
• Subjects: Accumulation; Amaranthaceae - growth & development; Amaranthaceae - metabolism; Amaranthaceae - radiation effects; Anthocyanins; Anthocyanins - analysis; Biomass; Blood vessels; Brazilian ginseng; Carotenoids - analysis; Catalase - metabolism; Cell walls; Chlorophyll - analysis; Chromatography, High Pressure Liquid; Ecdysterone - analysis; Electron transport; Endangered species; Fructose; Light; Light effects; Light emitting diodes; Light quality; Light sources; Light-emitting diode; Metabolism; Metabolites; Micropropagation; Morphogenesis; Organic light emitting diodes; Oxidative stress; Pfaffia; Photosynthesis; Phytoecdysteroid; Plant Leaves - chemistry; Plant Proteins - metabolism; Plant Roots - chemistry; Plant Roots - growth & development; Plant Stems - chemistry; Plant tissue culture; Plants, Medicinal - growth & development; Plants, Medicinal - metabolism; Plants, Medicinal - radiation effects; Secondary metabolites; Shoots; Starch; Starch - metabolism; Sucrose; Sugar; Superoxide Dismutase - metabolism; Thickening; Xylem
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2019.111761

The combination of different colors from light-emitting diodes (LEDs) may influence growth and production of secondary metabolites in plants. In the present study, the effect of light quality on morphophysiology and content of 20-hydroxyecdysone (20E), a phytoecdysteroid, was evaluated in accessions of an endangered medicinal species, Pfaffia glomerata, grown in vitro. Two accessions (Ac22 and Ac43) were cultured in vitro under three different ratios of red (R) and blue (B) LEDs: (i) 1R:1B, (ii) 1R:3B, and (iii) 3R:1B. An equal ratio of red and blue light (1R:1B) increased biomass accumulation, anthocyanin content, and 20E production (by 30–40%). Moreover, 1R:1B treatment increased the size of vascular bundles and vessel elements, as well as strengthened xylem lignification and thickening of the cell wall of shoots. The 1R:3B treatment induced the highest photosynthetic and electron transport rates and enhanced the activity of oxidative stress-related enzymes. Total Chl content, Chl/Car ratio, and NPQ varied more by accession type than by light source. Spectral quality affected primary metabolism differently in each accession. Specifically, in Ac22 plants, fructose content was higher under 1R:1B and 1R:3B treatments, whereas starch accumulation was higher under 1R:3B, and sucrose under 3R:1B. In Ac43 plants, sugars were not influenced by light spectral quality, but starch content was higher under 3R:1B conditions. In conclusion, red and blue LEDs enhance biomass and 20E production in P. glomerata grown in vitro. [Display omitted] •A 1R:1B ratio increases content and production of 20E by 30–40% in P. glomerata.•A 1R:1B ratio increases biomass, anthocyanins, and lignification of vascular tissue.•A 1R:3B ratio improves photosynthesis, electron transport, and antioxidant activity.•Primary metabolism responds differently to spectral quality in Ac22 and Ac43 plants.