Vol. 5, Issue 4 (2020)
Establishment of in vitro mass propagation protocol in Micropera obtusa (Lindl.) Tang & Wang
Author(s): Tapash Kumar Bhowmik, Md Mahbubur Rahman
Abstract: Endangered orchid Micropera obtusa (Lindl.) Tang & Wang seeds on the entire four agar solidified KC; MS; PM and MVW nutrient media with three different sources of carbohydrates viz. sucrose, glucose and lactose tried. Maximun seed germination (70%) was however, recorded on PM medium followed by MS (60%) and MVW (60%) media. The percentage of germination was considerably reduced on lactose supplemented KC medium (20%). Sucrose was found to be best response whereas lactose supplemented medium gave poor performance. With different concentrations and combinations of auxins, cytokinins added on agar solidified or liquid MS and PM media then germinated PLBs were cultured there. Highest shoot growth was recorded on liquid MS medium supplemented with 1.0 mg/l IAA and 1.0 mg/l BAP (2.60 ± 0.10 cm) followed by agar solidified MS + 1.0 mg/l NAA + 1.0 mg/l BAP (2.37 ± 0.15 cm). Liquid culture was superior than agar solidified condition and MS was found better than PM medium for elongation of in vitro grown germinated PLBs. Full strength agar solidified MS with 0.5 mg/l NAA produced highest increased length and number of roots (4.63 ± 0.28 cm/shoot bud and 2.53 ± 0.17 no/shoot bud) followed by half strength hormone free MS medium (4.03 ± 0.22 cm/shoot bud and 2.32 ± 0.12 no/shoot bud). The well-developed seedlings were transferred to outside environment and watered regularly.