Analysis of the relationship based on
133 RAPD loci revealed that the genetic
distances among 19 genotypes ranged
from 0.094 (90.6% similarity) to 0.344
(65.6% similarity) (data not shown).
Genetic divergence among restorers
from 0.094 to 0.269, while that among
restorers from 0.143 to 0.197. CMS
group showed the most diversity that
varied from 0.134 to 0.344. The RAPD
cluster pattern is presented in Fig. 3. It
showed five clusters at the cut off 0.20
genetic distance level and eight clusters
at the cut off 0.17 genetic distance level.
All the TGMS lines were grouped in one
cluster at 0.20 level, but they were
divided into two sub-clusters according
to their parentage relationship at 0.17
level. Two CMS lines, IR68281A and IR69617A, which were developed
through genome substitution of
IR58025A by repeated back crossing to
male parents IR54718-C3 and IR54718-
C2, respectively, were closely clustered
together with the genetic distance of
0.134. These two CMS lines might be
considered as sister lines derived from
the same ancestral origin. Four leading
CMS lines viz. IR62829A, IR54755A,
IR58025A and PMS2A formed two
clusters. The cluster of IR54755 A and
IR62829A was genetically much more
closer to TGMS cluster as compared to
the cluster of IR58025A and PMS2A.
However, despite being in the same
cluster, the genetic similarity between
IR54755A and IR62829A is only 76.6%.
Pant CMS2A was grouped into the same
cluster with seven other genotypes at
0.20 level but it was separated into
distinct sub-cluster at 0.17 level