Rhynchostylis retusa, a valuable ornamental, medicinal, and endangered orchid is rich with bioactive compounds which are potential raw
materials for pharmacological utilization. In the present study, application of organic additives for the enhancement of seed germination and
seedling formation in the species was assessed through asymbiotic culture and an efficient protocol for its rapid propagation using
immature seeds procured 8 wks after pollination (wap) was developed. Four different nutrient media namely Mitra et al. (M, 1976), Modified
Knudson C (KC, 1946), Murashige and Skoog (MS, 1962), and Vacin and Went (VW, 1949) were used to investigate the effects of different
organic additives i.e. Yeast Extract (YE; 1 gl-1), Peptone (P; 1 gl-1), Casein Hydrolysate (CH; 1 gl-1), and Activated Charcoal (AC; 2 gl-1)
during asymbiotic seed germination and subsequent seedling development. The seeds of the presently investigated species successfully
germinated in all the nutrient media used. Highest seed germination (88.00%) and early seedling formation (129.50±0.64 days) was
observed in VW medium followed by M (87.25%; 137±0.47 days), MS (79.25%; 148±0.40 days), and KC (73.75%; 157.25±0.47 days)
media respectively. Based on present results, the optimal nutritional combination during germination, growth and subsequent development
into seedlings of R. retusa is suggested as VW medium supplemented with P (1 gl-1). An efficient propagation protocol formulated for the
species may be utilised as a useful guide for similar studies in other related orchids.
https://doi.org/10.64873/JOSI.v35.i1-2.99-107