In vitro potato plantlet development under different polychromatic LED spectra and dynamic illumination

We studied growth of potato plantlets of two cultivars under different constant polychromatic light-emitting diodes (LEDs) and dynamic lighting with the spectrum modifications during growth. Light sources constructed by us were sunbox SB, red-green-blue RGB, and full spectrum FS, red-blue. White luminescent lamps were used as control light. Dynamic lighting was achieved by transferring groups of plantlets from one box to another. Red/green/blue portions in the light sources were (in percents): 39R/39G/22B for SB, 63R/21G/16B for RGB, 74R/8G/18B for FS, and 22R/49G/29B for control. PPFD was set at 45 μmol/m2 s. Morphometric measurements were made 14 and 28 days after planting. Plantlets developed differently from initial stages. Cultivar 'Red Scarlett' appeared to be more susceptible to different lighting than 'Innovator'. Light variations RGB and RGB-SB were the most favorable for plantlet development. This is the first report on the dynamic lighting application for growing potato plantlets.