A Protocol for In Vitro Plant Regeneration in Ocimum basilicum L.: A Medicinal Herb
S. Sudhakaran *
Department of Biotechnology, Asian Institute of Medicine, Science and Technology No. 2 Persiaran Cemphaka, SG PETANI, 08000, Kedah, Malaysia
V. Sivasankari
Department of Biotechnology, Center for Biological Sciences, K.S.R. College of Arts and Science, Tiruchengode 637 209, TN, India
*Author to whom correspondence should be addressed.
Abstract
The present study is aimed to develop a reproducible protocol for callus induction, regeneration and micropropagation of Ocimum basilicum (Lamiaceae). Callus initiation from the leaf and internodal explants were observed after 15 days from the cut faces of the explants inoculated on MS basal media supplemented with 2mg/l 2,4-D and 1mg/l kinetin. Various types of calli formed viz. White friable, compact and nodular calli were observed. From the nodal explants, axillary bud break was observed and the buds developed into shootlets within 30 days. Of the 2 explants used for micropropagation, apical buds showed minimum response whereas the nodal explants exhibited maximum response. Bud break (90 %) with callusing was observed from nodal explants whereas apical buds showed a slow growth and some callusing. Of the two cytokinins used, both BAP (2 mg/l) and Kinetin (1.5 mg/l) were 100 % responsive in shootlet formation. Length of the Shoots was more in kinetin supplemented media whereas BAP supplemented media showed reduced shoot length. Multiple shoots were also observed in some nodal explants where the BAP supplementation is 2 mg/l and Kinetin concentration is 1.5 mg/l. NAA (3mg/l) was found to be more suitable for rootlet formation.
Keywords: Axillary bud break, Callus, Micropropagation, Multiple shoots, Ocimum basilicum