IN VITRO MICROPROPAGATION OF VANDA ROXBURGHII: A MEDICINAL ORCHID OF THE WESTERN GHATS AND DETERMINATION OF GENETIC FIDELITY USING RAPD MARKERS
Dhananjaya Sasalu Panchaksharaiah*, Gururaj Chalageri and Uddagiri Venkanna Babu
Objective: An competent in vitro protocol was developed for rapid multiplication of medicinally and commercially important rare orchid, Vanda roxburghii R.Br., cost effective method was adapted for acclimatization and fidelity test to confirmed genetic similarities. Methods: Different types of media fortified with 10% coconut water (CW) and casein hydrolysate (CH) were used for seed germination as well as PLB formation. MS medium with different auxins i.e. 2,4-D and NAA alone were used for callus induction from leaf explant. Callus were subcultured on Terrestrial Orchid Media (TOM) supplemented with cytokinins and activated charcoal (AC) will yield PLBs and shoot formation. For root development, shoots were subcultured on TOM fortified with BAP along with different concentration of NAA and IAA were analyzed. Results: The maximum seed germination (87%) and PLBs was observed in MS medium fortified with 10% CW and CH 3.28M. Well-developed callus formation was achieved on MS supplemented with 2,4-D (2.27 μM). The PLBs and shoots were observed from the callus on TOM with BAP (8.88 μM) and AC (8.3M). Well-developed root with shoots were observed on TOM fortified with BAP at 8.88 μM with 8.05 μM NAA. The novel brick base method adopted for primary acclimatization and 95% survival frequency were observed. The genetic uniformity was confirmed through RAPD profile. Conclusion: The present investigation provides a commercially viable protocol for this species with adopting novel technique for acclimatization process and field trials. The RAPD results confirms similarity of genome in vitro plants.
Keywords: Acclimatization, indirect regeneration, orchid seed germination, protocorm like bodies, Vanda roxburghi.
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