Heritability and genetic advance of some grain yield components and some
morpho-physiological traits in 36 sorghum hybrids [Sorghum bicolor L.
Moench] produced by top-cross using cytoplasmic male sterility were
estimated.
Narrow-sense heritabilit
y for plant height and head length were relatively
high in Damascus location (65% and 56%) respectively, but the narrow-sense
heritability of all characters in Raqqa location were low, the range was from
3% for threshing percentage to 34% for plant height, and from 22% for seed
weight/head to 60% for plant height in the combined analysis.
Genetic advance estimates were relatively low for all characters, the range
was from 0% for 100 seed weight to 28.3% for plant height (Damascus
location), and from 0.02% for seed numbers/head to 15.2% for plant height
(Raqqa location), and from 5.8% for the number of days to flowering to 26.5%
for plant height (combined analysis).
Some characters such as plant height and head length showed relatively
high values of heritability, but exhibited low values of genetic advance.
Therefore other characters had low heritability coupled with low values of
genetic advance indicated predominance of non-additive gene action. This
result implies the need for several generations of selection to improve grain
yield components and other traits.
This study was conducted at the General Commission Of Scientific
Agricultural Research (GCSAR) for tow consecutive years, 2000-2001, to
estimate the heterosis of some sorghum hybrids utilizing cytoplasmic male
sterility technique, and to determine
the behavior of the parents used in
hybridization concerning their relation to the cytoplasmic male sterility.
Hybrids were planted in a randomized complete block design, including 43
hybrids in tow replications.
The results showed variation among parents characters, because they were
selected from different environments and also differ in genetic components.
positive heterosis was recorded form crosses involved foreign parents with
local ones, or foreign hybridized with foreign. positive heterotic values for
earliness and productivity were obtained .
The genetic constitution of the male parent was assessed as R-line (restoring
of the A-line), and B-line (maintainer of the A-line).
