Qualitative assessment of tissue culture parameters useful in transformation of indica rice

In vitro response of several elite indica rice cultures was compared with that of the most responding japonica type, Taipei 309, for enumerating critical tissue culture parameters that subscribe to successful genetic transformation. Callus induced from mature seeds of indica rice genotypes was more compact and proliferated slowly. Formation of friable callus, rapid proliferation and sustenance of regeneration capacity for 9-10 weeks, are identified as the key features that favour success of transformation in a variety and recovery of transformant through subsequent selection and regeneration. Differences in regenerating and nonregenerating green regions were presented to differentiate them at the early stages.