Effect of Cryoconservation on Seed Germination of Rare Tropical Orchids

In search of a procedure for cryoconservation, seeds of five species of tropical orchids and of one intergeneric hybrid were germinatedin vitroas depended on illumination. The other portion of seeds was frozen in liquid nitrogen (–196°C) and germinated after thawing. The viability of seeds, the percentage and rate of germination, as well as the growth rate of the developed protocorms were evaluated. At early stages of development, light inhibited growth in most species examined. The storage of seeds in liquid nitrogen had no negative effect on growth and development of protocorms and juvenile plants. The feasibility of the conservation of mature seeds of some tropical orchids by freezing in liquid nitrogen was demonstrated, which offers opportunities for creating a cryobank of orchids.