In vitro asymbiotic propagation of the vulnerable slipper orchid Cypripedium cordigerum D. Don

This paper presents an attempt to establish a protocol for the conservation of Cypripedium cordigerum D. Don a vulnerable species of orchid using in vitro symbiotic seed germination. The suitability of four orchids seed germination media [Terrestrial orchid medium (BM), modified terrestrial orchid seed germination medium (BM-1), Malmgren modified terrestrial orchid medium (MM), Knudson C medium (KC)] was tested using different photoperiods i.e. 24-h dark or 12-h light per day. The seed capsules were harvested at two different stages of development in order to determine the effect of capsule maturity on seed germination. The maximum percentage germination of seed from intact capsules in the dark was 65.00 ± 0.12% on the BM-1 medium. Release of brownish exudates was stopped by the addition of activated charcoal to the cultures. Seedlings developed in 26.17 ± 0.17 weeks. The current study is the first to report the ex-situ conservation of C. cordigerum.