PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

Three different plants, viz. Jute (Corchorus olitorious; variety JRO-524), Dahlia sp. (winter annual), Heritiera fomes (halophyte), from three different eco-habital conditions were studied to understand the underlying mechanism of three fold checkpoints for in vitro plant regeneration, i.e., callus initiation, shoot differentiation and root formation. The whole procedure of tissue culture was carried out with minimum infrastructural facilities, in order to simulate the natural conditions in the laboratory. Only Jute plant in this set up could overcome all the three aforesaid specific checkpoints and gave healthy tissue cultured plants. Dahlia could cross the first two checkpoints, but failed to produce roots during February-March. As the inoculation proceeded the natural germination period of Heritiera, regeneration was delayed; callus formation initiated only when the environmental conditions of the culture system mimicked that of its normal growing season. We believe that Jute could cross all the three checkpoints because the explants were inoculated during its normal growing its normal growing season. We also observed in this protocol, morphologically abnormal callus formation in Jute takes place, when cultured in the same system, but in a time different from that of its normal growing period. Time proper tissue culture following environmental condition thus helps �true to the type� plantlet regeneration in minimal time.