Effect of 6-benzylaminopurine and -naphthalene acetic acid hormonal supplements on the in vitro seed germination and seedling development of orchid Otochilus albus Lindl

Otochilus albus Lindl is one of the important orchids especially used for the horticultural purpose and commercial use. It is listed as a rare and critically endangered species in Nepal. An attempt to preserve the important orchids was done by establishing an efficient in vitro regeneration protocol using seed. This study was carried out by using Murashige and Skoog (MS) medium and the MS medium supplemented with growth regulators namely 6-benzylaminopurine (BAP) and α-naphthalene acetic acid (NAA) in different concentration. The seed germination and protocorm formation started after 8 weeks of culture, and complete seedling was developed within 26 weeks of culture in the basal medium and medium supplemented with 0.5 mg/L BAP and 0.5 mg/L BAP + 0.5 mg/L NAA, respectively. Regardless of the NAA supplement, the protocorm formation and seedling development were delayed in the medium containing higher concentration of BAP. Key words: Otochilus albus Lindl, in vitro, Murashige and Skoog (MS), 6-benzylaminopurine (BAP), α-naphthalene acetic acid (NAA).