Evaluation of somaclonal variants for yield and some quality parameters

A field experiment was conducted to examine the variability of eight somaclones for agronomic and quality parameters. A significant reduction in plant height and days to flowering was noted. There was increase in kernel length and head rice recovery. TF4 was selected having stiff stem, early in flowering, semi dwarf with high fertility, better grain quality and greater yield potential than the parent variety. TF8, TF9 and SN12 yielded at par with the parent variety i. e. Basmati 370. Profuse but unproductive tillers did not contribute to the yield. Linear relationship existed between increased L/B ratio and better grain quality. The grains of all the somaclones were fine type, slender in shape and long in size. The highest quality Index was exhibited by TF9 followed by TF11 and TF10 respectively

Tissue culture of Pakistani rice varieties: I- Optimization of physical factors

A study for optimizing appropriate explant, conditions for sterilization and physical environments was conducted using rice varieties Bas -370, IR-6 and KS-282. Sterilization of seeds was better obtained in HgC12 than chlorox [Commercial sodium hypochlorite] but due to lesser seed germination after HgC12 treatment, chlorox was prefered over the other. Chlorox treatment increased the subsequent callus induction in seeds. However, nodal portions and root tips were damaged by the treatments. Out of mature seeds, nodal explants and root tips, seeds proved to be the best explant for callus cultures, 28°C was the best temperature for callus induction and callus multiplication in the seeds. However for organogenesis 26°C was the optimum. Light, complete dark or 16 h day length played no significant effect in callus induction. Callus formation frequency was maximum at a pH ranging from 5.5 to 7.0. Beyond this pH range there was a sharp decline in callus induction, multiplication and plant regeneration