In vitro propagation and forest reestablishment of Cymbidium finlaysonianum Lindl., an endangered medicinal orchid

Abstract

© 2018, Walailak University. All rights reserved. An in vitro plant regeneration protocol was successfully established for Cymbidium finlaysonianum Lindl., an epiphytic endangered medicinal orchid, by culturing seeds from 4-month-old green self-pollinated fruits. Tetrazolium (TZ) viability test indicated a mean embryo viability of 97.80%. Three asymbiotic orchid seed germination media, namely Knudson C medium (KC), New Dogashima medium (ND), and Vacin and Went medium (VW), were studied to select a suitable medium for seed germination. The highest seed germination percentage was 83.8 % on VW medium. Protocorm-like bodies (PLBs) of C. finlaysonianum Lindl. induced from protocorm segments cultured in VW liquid medium supplemented with 8.84 μM BAP gave the highest % PLB formation and number of PLBs per explant, at 85.7 and 5.2, respectively. VW medium supplemented with 0.2 % (w/v) activated charcoal (AC) gave the highest number of roots per plantlet and root length, at 6.4 roots and 5.2 cm, respectively. The highest percentage of plantlet survival recorded at 24 months after reestablishment in the forest was 71.6%.