THE INFLUENCE OF LIGHT QUALITY IN THE in vitro CULTIVATION OF Cattleya crispata

ABSTRACT: Micropropagation technique is a valuable alternative for high quality genetic preservation of endemic species such as the orchid Cattleya crispata from “Campo Rupestre Ferruginoso”. This study aims to evaluate the influence of light quality on in vitro multiplication and elongation phases, offering new insights on the limiting factors of C. crispata. Seeds extracted from capsules were used for inoculation in the culture medium. Four light sources were evaluated for in vitro culture, namely: fluorescent lamp, white LEDs, red LEDs and red/blue LEDs. Data about the number of shoots, shoot length, shooting vigor and pigment content were assessed at 90 days of in vitro culture. Based on the recorded results, white LEDs are the most suitable ones for in vitro multiplication and elongation phases of C. crispata. It offers higher quality for seedling production and increases the chances of genetic conservation of the species. Keywords: ‘Campo Rupestre Ferruginoso’; in vitro propagation; wavelength; LEDs