Abstract:
Dragon fruit (Hylocereus undatus) (Cactacea) is a climbing vine which has received worldwide attention, first, as an ornamental plant and then extended as a fruit crop. Since seed viability of stored dragon fruit is very low, stem cuttings are used as planting material in Dragon fruit. Though several studies
have examined different propagation methods for Dragon fruit; very little information is available on
protocols for production of high quality planting material via tissue culture. In the present study we
examined the potential of direct shoot regeneration of Dragon fruit explants using leaf and stem cuttings obtained from in vitro germinated seedlings in 3 different concentrations of Benzylaminopurine
(BA) 2, 2.5, 3mg/l supplemented with 0.01mg/l NAA to the Murrashige and Skoog (MS) basal regeneration medium. Thereafter regenerated plantlets from direct organogenesis from all explants were rooted
in MS basal medium supplemented with 0.01mg/l NAA (Naphthaleneacetic acid).
Results revealed that the type of explants greatly influences the regeneration ability of shoot buds. Stem
explants exhibited much higher regeneration ability (18 buds/explant) than leaf explants (3 buds/
explant) without vitrification. Within 4 weeks, buds were initiated on explants on MS basal medium
supplemented with 2.5mg/l BA and 0.01mg/l NAA and buds took nearly 60 days to elongate to 1.5cm on
the same medium. Stem and leaf explants, regenerated the highest number of shoots on MS medium
supplemented with 2.5mg/l BA and 0.01 NAAmg/l compare to that of the other hormone combinations.
Rooting was observed in regenerated mature shoots after transferred onto MS basal medium with
0.01mg/l NAA.
