Light Quality Affects Growth and Physiology of Carpesium triste Maxim. Cultured In Vitro

The objective of this study was to investigate the effect of light quality on the growth and contents of photosynthetic pigments and total flavonoids, the parameters of chlorophyllafluorescence, antioxidant capacities, and enzyme activities. It was intended to preliminarily explore the internal mechanisms involved for the effect of light quality on the growth and physiology ofCarpesium tristeMaxim. Stem apex explants were cultured on the Murashige and Skoog (MS) medium under white (W), red (R), blue (B), or a 1:1 mixture of red and blue (RB) light-emitting diodes (LEDs) for four weeks. The RB induced sturdy plantlets and increased the contents of photosynthetic pigments and total flavonoids, photosynthetic electron transport and efficiency, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging capacity, and activities of antioxidant enzymes in the plantlets. Taken together, combinations of monochromatic red and blue LEDs could be used for the best production of high-qualityC.tristeplantlets in vitro.