Microscopic Studies of in vitro Seed Germination and Protocorm development in Dactylorhiza hatagirea (D. Don) Soo:A critically Endangered Medicinal Orchid of Northwestern Himalaya

摘要

Dactylorhiza hatagirea (D. Don.) Soo is a critically endangered medicinal orchid of Northwestern Himalayan region. Dactylorhiza hatagirea is one of the very few orchids known for its therapeutic and medicinal significance. In nature, D. hatagirea plant regeneration takes place through seeds but the seeds are minute and without endosperm, therefore, mycorrhizal association is needed for germination; as a result they do not germinate readily. In the present study, seed germination and protocorm development was standardized under in vitro conditions. Combination of 2-iP (0.5 mgl~(-1)) and with BA (1.0 mgl~(-1)x) showed better performance in terms of per cent survival, multiplication and growth of proto-corms. Formation of protocorm and initiation of shoot meristem was observed in 70±5 days. Light and Scanning electron microscopic studies were also performed to describe the stages of germination, development of shoot apex and leaf primordia in a 225+3 days old protocorm.