Asymbiotic germination and seed storage of Paphiopedilum insigne, an endangered lady's slipper orchid

The present scenario of urbanization and commercialization has adversely affected orchid's population; as a consequence they are diminishing from the nature very rapidly. Paphiopedilum insigne (lady's slipper orchid) is one such orchid of horticultural importance. Apart from being listed as endangered in IUCN red data list; it finds a place in Appendix I of CITES in the global platform. In the present study, capsules < 180 days after pollination (DAP) were found to be immature and 180 DAP was found optimal for seed germination. Capsules > 240 DAP were found to have mature seeds that were treated prior to germination and TTC tested for viability. Seeds derived from 180 DAP capsules showed the highest germination of 88.5% in modified Burgeff medium (BG1) with initiation in 26 days. Incorporation of plant growth regulators like 5 μM kinetin (KN) + 10 μM indole-3-acetic acid (IAA) in 1/2 MS medium influenced the stage-wise development of the seedlings in a short duration. Mature seeds stored at − 196 °C for 360 days followed by pre-treatment with 3% NaOCl showed viability of 70.5% and recorded germination of 79.2%. Sixty-nine percent of the plantlets were successfully hardened and acclimatized in the green house.