The submergence testing of both genotypes produced
predictable results. All the untreated somaclones of
FR13A and FR43B survived complete submergence.
There was a decrease trend in the survivability of the
somaclones with increase in gamma radiation dose. This
is because high radiation may be mutating the DNA
sequence responsible for expression of submergence
tolerance. When the somaclones were analyzed for the
presence of a specific sequence pdc1 for submergence
tolerance, only a proportion of the somaclones amplified
in both the genotypes. The plant without pdc1 gene amplification
must have a distortion of the DNA in the said
sequence due to gamma radiation. This can be proved by
performing RTPCR expression analysis or western
blotting technique. Further studies on these somaclones
both at the sequence level (by sequencing the gene
portions involved) and also at the plant level is required to
see that whether these plants still retain the submergence
tolerance of the parental genotype or not. The
extension of these studies will greatly help in understanding
the sequence information as well as its relationship in the expression of the genes concerned with
submergence tolerance.