Light condition, flask sealing, and cultivation time on the germination and initial in vitro development of Dendrobium nobile Lindl.

Abstract

Abstract One of the obstacles for the production of Orchidaceae plants is the seed propagation. Thus, in in vitro cultivation, luminosity and the type of sealing of the bottles are factors that influence germination and initial development of orchids. Therefore, the objective was to evaluate the light condition, the type of sealing of the bottles and the evaluation time in germination and initial in vitro development of Dendrobium nobile Lindl. After sowing, cultures were subjected to two irradiance conditions according to the sealing of the flasks: 7.0 µmol m-2 s-1 (threaded cap) and 19.0 µmol m-2 s-1 (plastic film) and two light conditions: white fluorescent lamp and red fluorescent lamp. At 30, 60 and 90 days, the percentage of germination, survival, of protocorms in stage 1, stage 2, stage 3 and stage were evaluated 4. DIC was used, in a sub-divided plot scheme for 30 and 60 days after sowing and in a 2 x 2 factorial scheme at 90 days. The highest germination percentage was observed when using white fluorescent lamp with a plastic film cover (70.33%) and at 30 days (70.13%). The highest survival percentage (100%) was observed when using plastic film cover and white fluorescent lamp at 90 days. The greatest development of propagules, reaching stage 4 was verified in the red fluorescent lamp with threaded cap (9.55%).