Protocorms encapsulation of Phalaenopsis hybrids (Orchidaceae) in order to schedule in vitro plantlet production

Artificial seed production is an alternative technique for asexual propagation and conservation of plants with difficult natural seed propagation system, such as orchids. This technique is rapidly growing in germplasm conservation and plant gene pool exchanges between countries and in vitro floriculture trades. Artificial seed is formed by encapsulating somatic embryo with coating materials. Quality, durability and survival of artificial seed are very important and depend on the kinds of explant, concentration of encapsulation materials and other conditions. In this study, the effects of different sodium alginate (3, 4 and 5%) and calcium chloride (75, 100 and 150 mM) concentrations for capsule gel matrix were investigated on conversion capabilities and germination of Phalaenopsis artificial seeds. The ideal beads were obtained through a combination of 4% sodium alginate and 150 mM calcium chloride. Encapsulated protocorms showed the best germination percentage (100%) on MS medium after 3 weeks. Storage of synthetic seeds after desiccation significantly reduced the viability percentage of seeds and protocorms. Treatment with autoclaved distilled water after desiccation and storage resulted in high viability percentage in protocorms, whereas dehydrated protocorms were found to be less tolerant to the storage.