A comparative study on karyology of
Pennisetum typhoides and
P. purpureum and their hybrid and amphiploid revealed considerable differences in the size, shape and position of centromere of the chromosomes of the constituent genomes. The diploid and tetraploid parents exhibited quantitative differences in size in respect of chromosomes of the homologous genomes A and A' and this was evident in the F
1 hybrid. The cultivated species
P. typhoides possessed more of asymmetry in karyotype than the wild species. The chromosomes of ‘B’ genome of
P. purpureum also exhibited asymmetry but less than the ‘A’ genome.
The concommittant morphological specialisation and the asymmetry of karyotype in
P. typhoides (AA') also point out that dominant features of
P. purpureum resident in ‘B’ genome and less specialisation appear to be associated with symmetry of B' genome. The changes in the karyological features in the F
1 and its amphiploid were not as expected to the value of parents. It is concluded that the alteration of the karyotype might be due to hybridity and would suggest alteration of the genetic control in expression of somatic complement.
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