EFFECT OF ENVIRONMENTAL-FACTORS ON IN-VITRO GROWTH AND MORPHOLOGY OF OTACANTHUS-COERULEUS (SCROPHULARIACEAE)

In order to determine the most important environmental conditions for the micropropagation of the ornamental Otacanthus coeruleus, the effec ts of some macro and micro environmental factors on in vitro growth an d morphogenesis were analysed. The growth increased both with higher t emperature (day/night 25/20 degrees C) and irradiance (55 mu mole.m(-2 ).s(-1)), and it was found to be the highest in the medium containing 6 g.l(-1) agar, 30 g.l(-1) sucrose and 10.7 g.l(-1) mannitol, with a m acronutrient concentration equal to that of Murashige and Skoog's medi um. The morphology of the explants was not so influenced by the tested temperature and irradiance levels, but by the agar and sucrose concen tration, and especially by the macronutrient concentration.