PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

An effective protocol for clonal multiplication from leaf explants of Datura metel was achieved by organogenesis as well as somatic embryogenesis. Two morphologically distinct types of callus � yellowish brown non-organogenic and green nodular organogenic calli were obtained in different combinations and concentrations of Indole-3-acetic acid (IAA) and 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP), Kinetin (Kn), Thidiazuron (TDZ). Green nodular organogenic callus was obtained when MS medium was supplemented with different concentrations and combinations of IAA (11.47 - 22.84�M), BAP (0 - 2.22�M) and Kn (0 - 2.32�M). These calli subsequently developed shoots without any change in the medium. Adventitious shoots were also obtained directly from leaf explants when cultured on MS medium supplemented with varying concentrations of IAA (22.84�M), BAP (3.33 - 8.88�M) and Kn (2.32�M). When higher concentrations of Kn were supplied (3.33 - 9.29�M) along with IAA at 22.84�M and BAP at 2.22�M, a protocorm-like structure was produced. Kinetin and BAP combination produced somatic embryos. When callus phase shifted to organogenic phase, starch and soluble sugar contents decreased indicating utilization of energy reserves during organogenesis. For micropropagation, in terms of number of plantlets produced, organogenesis via callus was found to be better than somatic embryogenesis or direct shoot organogenesis.