TITLE:
In Vitro Propagation of Ocimum Gratissimum L. (Lamiaceae) and Its Evaluation of Genetic Fidelity Using RAPD Marker
AUTHORS:
Soumen Saha, Abdul Kader, Chandan Sengupta, Parthadeb Ghosh
KEYWORDS:
Micropropagation; Multiple Shoot; Nodal Explant; Histology; Genetic Fidelity
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.3 No.1,
December
31,
2011
ABSTRACT: An efficient plant propagation system through nodal explants was established in Ocimum gratissimum L, a medicinally important herbaceous perennial herb belonging to the family Lamiaceae. Axillary shoot bud proliferation was initiated from nodal explants cultured on Murashige and Skoog (MS) medium supplemented with various concentrations of N6-benzyladenine (BA) (0.5 - 3.0 mg/l), Kinetin (KN) (0.5 - 3.0 mg/l) and 2-isoPentenyladenine (2-iP) (0.5 - 3.0 mg/l). Maximum numbers of shoots (5.17 ± 0.04) with average length (2.50 ± 0.07) were induced on medium containing 1.0 mg/l BA. Shoot multiplication was maintained by repeated subculturing the original nodal explants on shoot multiplication medium after each harvest of newly formed shoots. Histological study shows that the organogenesis occurs directly, without callus formation on epidermal and sub epidermal layer of the explants. Rooting of shoots was achieved on half strength MS medium supplemented with 1.5 mg/1 Indole-3-butyric acid (IBA) and 2% sucrose. Well-developed complete plantlets were transferred to plastic pots containing a mixture of (1:1) soil and vermiculite showed 82.5 % survival rate. Genetic fidelity was assessed by chromosome analysis and DNA fingerprinting using random amplified polymorphic DNA (RAPD) of in vitro and in vivo plants. Nine arbitrary decamers displayed same banding profile showed no genomic alterations, indicating homogeneity among the tissue culture regenerates and genetic uniformity with that of donor plants. The present study provides high fidelity micro-propagated system for efficient and rapid micro-propagation protocol of this important medicinal plant and great use in conserving without risk of genetic instability.