LUMINOSITY AND WATER IMMERSION IN THE INTERMEDIATE ACCLIMATIZATION FOR Dendrobium phalaenopsis Deang Suree

Resumo

Dendrobium phalaenopsis Deang Suree has good germination and development in asymbiotic culture medium, however his ex vitro adaptation still requires studies, because it causes dehydration of plants, delay their growth and development. The objective of this work was to study the combined effect of the immersion time in distilled water plant and two luminosity conditions in the treatment of intermediate acclimatization to D. phalaenopsis. Plants were divided into sets of 40, being subjected to immersion for 0, 12, 24, 36, 48, 60, 72 or 84 hours. After each immersion period the plants were transferred for containers containing the substrate planting and later allocated in growth room for intermediate acclimatization for 30 days. A set of 20 plants from each period of immersion and from the control remained under white fluorescent light (18.9 µmol m^-2 s^-1) and the other 20 plants remained under white fluorescent light + red fluorescent light (14.85 µmol m^-2 s^-1). After this period, the plants were subjected to acclimatization in greenhouse for 10 months. While immersion time increased the increments of fresh weight, pseudobulbs number and the roots number of plants grown under white light + red light decreased, while plants grown under white light did not show response with respect to immersion time. Absence of immersion in distilled water independently of luminosity condition is beneficial to plants of D. phalaenopsis Deang Suree.