In vitro plant regeneration from flower stalk explants of Phalaenopsis amabilis (L.) Bl

Abstract

An in vitro method was developed for plant regeneration of Phalaenopsis amabilis variety and hybrid using flower stalk cuttings. Experiments were conducted to overcome persistent contamination of stalks, break bud dormancy and induce regeneration of shoots. Results showed that incorporating 50 mg/l streptomycin in agar-solidified Vacin and Went (VW) medium inactivated of killed fungal and bacterial microorganisms that may have been left after sterilizing the stalks with 95% ethyl alcohol and 20% chlorine bleach. The stalk explants cultured in VW medium added with 5 mg/l benzylamino purine broke bud dormancy and induced the regeneration of shoots. The regenerated shoots exhibited three growth patterns, namely; vegetative, reproductive and dormant. The vegetative shoot produced multiple adventitious shoots in VW medium containing a combination of 5 mg/l benzylamino purine and 0.1 mg/l indole acetic acid. The regenerated shoots resembled the source plants and rooted easily in plant growth regulator-free medium. These were established in the screenhouse after acclimatization. The vegetative shoot has potential for clonal propagation of Phalaenopsis species.