The influence exerted by LEDs and fluorescent tubes, of different colors, on regenerative processes and morphogenesis of Rebutia heliosa in vitro cultures

Abstract

The paper traces how the light source and light color influence the regenerative processes and morphogenesis in vitro cultures of Rebutia heliosa. To establish the vitroculture of R. heliosa, some explants from young plants, either buds or rounds cut from young stems and cross-sectioned were considered. The culture medium consisted of: macroelements and Fe EDTA Murashige-Skoog (1962), microelements Heller (1953), a mineral mixture to which the following vitamins were added: pyridoxine HCl, thiamine HCl and nicotinic acid (each 1 mg/l, each), m-inositol – 100 mg/l, sucrose – 20 g/l and agar-agar 7 g/l, without growth phytoregulators.The variable element was the lighting source. Fluorescent tubes and LEDs (monochrome but differently coloured) have been used: blue (λ = 470 nm), yellow (λ = 580 nm), green (λ = 540 nm), red (λ = 670 nm) as well as LED`s emitting white light (λ = 510 nm) at a luminous intensity of 1000 lux. The evolution of R. heliosa vitro cultures was monitored for 90 days and analyzed their reaction variability. Based on the comparative study, the following can be stated: the light of fluorescent tubes is more suitable for the morphogenesis of R. heliosa vitroplants, but the processes of regeneration and organogenesis are directly influenced by the source and color of light influenced, thus rhizogenesis and caulogenesis is favored by the presence of green and red light emitted by LEDs, while the white and yellow light of fluorescent tubes favors the caulogenesis and callusogenesis processes.

Keywords

• callusogenesis processes
• fluorescent tubes
• leds
• roots
• young stem