in vitro propagation of Eria tomentosa (Koen.) Hook. f.: An important indigenous medicinal orchid of Bangladesh
MA Kashem, TK Bhowmik and MM Rahman
Stem and leaf segments of aseptically grown seedlings of Eria tomentosa(Koen.) Hook. f. gave response to both PGR supplemented agar solidified and liquid MS media and PM media. Both the explants underwent direct organogenesis producing shoot primodia like structures (SPSs) on MS medium fortified with 1.5-3.0 mg/l BAP or Kn either alone or in combination with 0.5-1.0 mg/l IAA or NAA. However, liquid MS + 3% (w/v) sucrose + 0.5 mg/l Pic + 1.0 mg/l BAP took lesser time and was effective for induction of shoot primordial than agar solidified PM. Liquid media were found more effective in SPSs induction. It was revealed that MS medium was more effective than PM medium for SPSs induction. The shoot primordia developed from stem and leaf segments underwent elongation when cultured on both liquid and agar solidified MS elongation media supplemented with different concentrations and combinations of PGRs and the maximum rate of elongation was achieved in MS (liquid) + 2.0 mg/l BAP + 1.0 mg/l IAA. The elongated shoots were produced aerial roots in agar solidified MS media supplemented with different PGRs. Thus an efficient protocol was developed for mass scale propagation of the selected orchid species.