ASYMBIOTIC GERMINATION OF CYPRIPEDIUM CALCEOLUS VAR. PARVIFLORUM (ORCHIDACEAE) IN VITRO.
Seeds from mature seed pods of Cypripedium calceolus var. parviflorum were germinated on 1/4 MSMO (Sigma) + 100ml/l coconut water + 1% sucrose +/- 8g/l agar (pH 6.0), and with or without prechilling at 5C for 8 weeks. Protocorm with apex (stage 3) was use as an index of germination. Seeds sown on agar medium withou chilling treatment resulted in a 40% germination rate in 120 days but the germination was very uneven. Seeds germinated on agar medium with prechilling developed more synchronously with 92% germination in 60 days (ie. about 120 days after sowing). Suspension culture of seeds without prechilling resulted in 85% germination after 90 days. The synchronization of seed germination in suspension culture was intermediate between that on agar with and without prechilling. Protocorms germinated in suspension culture appeared morphologically identical to those germinated on agar medium. All stage 3 protocorms developed further on the same agar medium in darkness. Both agar and suspension culture in media containing coconut water provided reliable seed germination methods for this orchid species.