IN-VITRO GROWTH OF CYMBIDIUM PLANTLETS CULTURED UNDER SUPERBRIGHT REDAND BLUE-LIGHT-EMITTING DIODES (LEDS)

The effects of light generated by superbright blue and red LEDs on the growth of Cymbidium plantlets cultured in vitro have been studied. Le af growth, chlorophyll content and shoot and root weights were affecte d by different LED irradiations. Red light promoted leaf growth but de creased chlorophyll content. This was reversed by blue Light. The grow th of Cymbidium plantlets in terms of increase in total shoot and root weights was comparable under red plus blue LEDs and the fluorescent s ystems. Generally, the response to different LED was similar for plant lets grown on sugar-free medium with or without CO2 enrichment and sug ar-containing medium but without CO2 enrichment. The growth of Cymbidi um plantlets was enhanced by CO2 enrichment. Our study demonstrates th e effectiveness of a total irradiation system for Cymbidium plantlets growth in vitro. The significance of our findings in relation to the d evelopment of a suitable lighting system for plant tissue culture is d iscussed.