SOME PHYSIOLOGICAL-PARAMETERS AND SEED LIPID-COMPOSITION OF TRANSGENIC TOBACCO PLANT

To see the effects of foreign gene introduction on the physiological p erformance and the quality and quantity of seed lipids, we studied tra nsgenic tobacco plant as a model system, as tobacco seeds are oil seed s. Using Agrobacterium Ti plasmid based vectors, tobacco plants cv Pet it Havana were transformed by NPT II gene as selectable marker. Transf ormed T-0, generation plants raised in tissue culture were transferred to pots and selfed. From the seeds, T-1 generation plants were grown in pots and their physiological performance was assessed. The transgen ic plants showed slightly slower rates of germination and growth. Tota l chlorophyll content, chlorophyll alb ratio and specific leaf weight, however, remained unchanged. The transgenic plants also had delayed f lowering. However, total protein, lipid content and fatty acid composi tion of lipids of seeds in transgenic plants did not show appreciable difference from the seeds from control plants. Thus the physiological cost of transgenic plant for the extra genetic load was only marginal, if any.