Abstract

Esmeralda clarkei is an epiphytic native orchid species of Nepal growing under medium amount of light with fragrant flowers. Reliable protocols for in vitro plant regeneration of E. clarkei via protocorm explants were developed. Protocorms obtained from in vitro germinated seeds cultured on Murashige and Skoog's (MS) medium supplemented with 6-benzylaminopurine (BAP) and α-naphthalene acetic acid (NAA) individually and in combinations responded positively by induction of multiple shoots. The cultures were maintained at 25 ± 2°C under a 16/8h light/dark cycle photoperiod provided by fluorescent lamps (Philips, India). BAP increased from 0.5 to 2.0 mg/l individually induced the maximum number of shoots (11 to 14 shoots per treatment) which is followed by combinations of BAP (0.5, 1.0 and 1.5mg/l) and NAA (0.5mg/l) which induced 7 to 8 shoots per treatment. The highest number of roots (3 roots per treatment) was observed in NAA (0.5 and 1.0 mg/l) supplemented medium among the other tested medium.

Key words: 6-Benzylaminopurine, Esmeralda clarkei, in vitro, α-naphthalene acetic acid, protocorm.

Abbreviation

ANOVA, Analysis of variance; BAP, 6-benzylaminopurine; IAA, indole-3-acetic acid; IBA, indole-3-butyric acid; MS, Murashige and Skoog medium; NAA, α-naphthalene acetic acid; SD, standard deviation; SPSS, Statistical Package for Social Sciences.