Production of Synseed for Hybrid Cymbidium Using Protocorm-Like Bodies

Synthetic seed were produced from protocorm-like bodies (PLBs) of hybrid Cymbidium Twilight Moon ‘Day Light’ after culture on a new medium, Teixeira Cymbidium (TC) medium. This new medium contained, in addition to a unique selection of macro- and micronutrients, 0.1 mg/l α-naphthaleneacetic acid and 0.1 mg/l kinetin, 2 g/l tryptone and 20 g/l sucrose, and was solidified with 8 g/l Bacto agar. Several explant types and sizes (intact PLBs, half-PLBs, PLB longitudinal thin cell layers) were tested. In addition, pretreatment of PLB-synseeds with 200 mM KNO3 solution, the addition of activated charcoal or coconut water to synseeds, light vs dark culture, short-term (1 month) and long-term (6 and 12 months) low-temperature (4°C) storage, as well as cryostorage were also tested. All treatments resulted in less PLBs than the control treatment. Among all these treatments, only the use of TC medium or incorporation of coconut water into synseeds resulted in “germination” while lowtemperature storage (1-6 months) was only possible under liquid TC. These results would allow for the short-term preservation of Cymbidium germplasm but not for effective cryopreservation.