Assessment of Adaptation, Regeneration Capability and Fatty Acid Profiles of LiCl Adapted and Unadapted Cell Lines of Oryza sativa L. Cv. Swat-1.

In the current studies calli of Oryza sativa. L. cv. Swat-1 were incrementally adapted to ionic stress (25 mM LiCl) to asses some of the adaptation mechanism(s). Adapted calli line was obtained on MS medium supplemented with 2,4-D (2 mg/l) and kinetin (0.25 mg/l). For regeneration MS medium with 1.0mg/l NAA and BAP + 30g/l D-Sorbitol was used. LiCl adapted line showed significantly higher indices of tolerance than unadapted line at 100, 150, 200 and 250 mM NaCl stress. Adaptation resulted in enhanced accumulation of saturated fatty acids (myristic and stearic acids), while unsaturated fatty acids exhibited variable profiles with enhanced oleic acid and significantly reduced linoleic acid. The regeneration capability of adapted line decreased 10 times (20% to 2%), while that of unadapted line kept on increasing (26% to 38%) at each subsequent subculture on regeneration medium. Addition of 10 mM LiCl resulted in enhanced and earlier regeneration in adapted line. Complete plantlets were obtained in about ten days while normally plantlets were obtained after 28 days. [ABSTRACT FROM AUTHOR]