ANALYSIS OF GENETIC STABILITY OF MICROPROPAGATED OCHRADENUS BACCATUS

Abstract

Ochradenus baccatus (Del.), an important medicinal plant, belongs to the
family Resedacea. Presently this is an endangered species therefore nonconventional
methods for their propagation are requested to prevent its eradication.
We developed a micropropagation method for mass multiplication of O. baccatus.
Explants collected from South Sinai were used to establish cultures of O. baccatus.
Surface sterilized nodal shoot segments and shoot tips were used for
micropropagation by culturing on Murashige and Skoog (MS) medium supplemented
with different concentrations and combinations of BA and 2ip. Stem node sections
were superior in enhancing formation of sub axillary shoots on MS medium
supplemented with 1.0 mg/l BA + 1.0 mg/l 2ip. The multiplied shoots were then
rooted on WPM supplemented with 1.0 mg/l IBA. The plantlets were acclimatized ex
vitro. Genetic stability of plants produced in vitro was evaluated using random
amplified polymorphic DNA (RAPD) analysis. Plants produced under different
concentrations of hormones, mother plant and the plants grown ex vitro were
analyzed by RAPD using 8 random 10-mer DNA primers. Results showed that 73
RAPD bands were obtained which gave 39.72 % polymorphism. The production of
variant plants is not good for commercial propagation. However, it could be
minimized by reducing the subculture cycle or by reducing hormone level in media.
Additionally, this variability could be used for further improvement and selection of
new cultivars and is an important source of variability to be exploited.