The success of tissue culture protocols based on ex vitro-derived Paphiopedilum explants is limited due to the rarity of materials, difficulties caused by bacterial and fungal decontamination and the poor development of explants that survive under in vitro conditions 6, 9, 10. armeniacum is currently listed as endangered in The IUCN Red List of Threatened Species, version 2014.3. armeniacum is a terrestrial or lithophytic orchid that is only distributed in the western part of Yunnan province, China, along the Nu River from Shidian county in the south to the North of Fugong county and the Southwest of Weixi county in the North and flowers from March to May in the wild 2, 8 ( Fig. armeniacum as the parent, 39 as seed parents and 85 as pollen parents 7. Currently (last assessed on September 6, 2015), 124 hybrids use P. Liu is one of the most fascinating Paphiopedilum species because of its characteristic golden flowers. Incidentally, the trade of all Paphiopedilum species, which are listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix I, is prohibited 4, 5, 6. This loss of suitable habitats is caused exclusively by anthropogenic activity in response to the trade of this orchid. Wild populations of Paphiopedilum are under the constant threat of extinction due to overcollection for use as ornamental plants or as breeding parents. The rarity, beauty and value of Paphiopedilum species, popularly known as slipper orchids, have always captured the interest of orchid growers and hobbyists. Paphiopedilum is a rare orchid genus, which is comprised of about 96–100 species around the world 1, 2, 3. Plantlets that were at least 5 cm in height were transplanted to a Zhijing stone substrate for orchids and 85.3% of plantlets survived 180 days after transplanting. Pretreatment of dry mature seeds (180 DAP) with 1.0% sodium hypochlorite solution for 90 min or 40 kHz of ultrasound for 8 min improved germination percentage from 0 to 29.2% or to 19.7%, respectively. Poor germination was displayed by 140 DAP seeds with a compact testa. The optimum basal medium for seed germination and subsequent protocorm development was eighth-strength Murashige and Skoog (1/8MS) for 95 DAP seeds and ¼MS for 110 DAP seeds. Suspensor cells were vacuolated, which enabled the functional uptake of nutrients.
Most seedlings (50%) developed to stage 5 from 110 DAP seeds whose compact testa had not yet fully formed. Seeds collected from pods 45 days after pollination (DAP) did not germinate while 95 DAP seeds displayed the highest seed germination percentage (96.2%). This study also examines the effect of media and seed pretreatments on seed germination and subsequent seedling growth. armeniacum zygotic embryos and their ability to germinate asymbiotically in vitro. This paper documents the key anatomical features during the development of P.