physicochemical

SAIDAIAH et. al.
results revealed that there is no direct relationship
between gca effects of parents and sca effects of
hybrid combinations. This can also be explained from
the point of gene action since gca is due to additive
gene action, whereas sca is due to dominance and
epistasis gene action.
The present investigation on interrelationship
of gca with sca revealed that predominance of non
additive gene action viz., additive x dominance and
dominance x dominance type for gene interaction for
most of the hybrid combinations, which could be
exploited for heterosis breeding programme in rice.
The lines APMS 6A and CRMS 32A and
testers1096, 612-1, GQ-70, GQ-120, KMR 3 and SG
27-77 could be used as potential donors in breeding
for improving grain yield and attributing traits. The
hybrids viz., APMS 6A x 612-1, PUSA 5A x KMR-
3, CRMS 32A x IR 43 were found to posses high
sca effects for grain yield and yield attributing traits
with at least one of the parent possessing positive
alleles. Hence these hybrids can be specifically
suitable for exploiting heterosis for increased grain
yield in rice in near future.
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