ABSTRACT

In the present investigation studies were carried out to determine the callus induction, growth and regeneration in two indica rice genotypes viz. Swarna and APMS6B. Studies were conducted to optimize various parameters for stable transformation in rice through Agrobacterium mediated gene transfer. Callus induction frequency in MS medium in light was higher than in dark irrespective of the genotype. Regeneration in both Swarna and APMS6B did not show much variation between calli induced in MS and N6 basal medium and incubation in light and dark.

Transformation of calli derived from mature seeds of two genotypes was attempted using  Agrobacterium EHA105/1304 plasmid containing Cry1AC and gus reporter gene was used for transformation studies. Gus expression was observed in two genotypes. Success of plant transformation using Agrobacterium depends on factors such as (i) concentration of Acetosyringone (ii) Concentration of Agrobacterium cells in culture. (iii) infiltration time and (iv) hygromycin in selection medium. Concentration of Acetosyringone, 100 mM and concentration of Agrobacterium cells, 2 x 108 cells/ml (OD = 2) with infiltration time of 30 minutes showed higher transformation rate. Present study thus indicates that genetic transformation in rice can be successfully achieved by optimizing various parameters for Agrobacterium mediated transformation. In the molecular detection study, F2 segregants of cross between BPT 211 and IR72 with a Xa21 were analysed for the native Xa21 gene by homozygous and heterozygous condition.