Indian Society of Genetics & Plant Breeding
The genetic analysis carried out according to variety cross
diallel model involving eight diverse maize composites
possessing various levels of tolerance to moisture stress
under optimum moisture and rainfed conditions revealed
that the variance due to dominance effect was significant
for days to 50% silking and tasseling, leaf area, plant
height, cob width under both moisture situations. Variance
due to additive effect, dominance effect GCA and SCA
were significant for grain yield and test weight under both
irrigated and rainfed conditions. The average heterosis x
mating interaction was significant for grain yield under
irrigated condition and for test weight for both the
conditions. In our study, A-68 was one of the parents
in crosses, which recorded highest heterobeltiosis under
rainfed conditions for grain yield, plant height, and Cob
width and cob length. The heritability values estimated
on individual diallel sets revealed that test weight, plant
height and cob width are highly heritable under both
irrigated and rainfed conditions. While, heritability for yield
was very low. The estimates of heritability also changed
with mating systems. Thus, for breeding for moisture
stress tolerance, indirect selection using highly heritable
and highly correlated traits with yield will be an effective
strategy. The correlation studies revealed that the grain
yield was positively and significantly correlated with test
weight, cob length, cob width, number of rows per cob
and number of grains per cob under optimum moisture
(14), limited moisture (12) and rainfed (10) situations. The
results revealed that cob width, number of grains per row
and test weight. were the common yield components
across different moisture regimes. The mUltiple regression
equation fitted to predict grain yield explained 47%, 37%
and 26% of the variation in yield under 14, 12, 10' respectively.
Thus, low leaf area in conjugation with more test weight,
cob width and grains per row form effective indirect
selection criteria for grain yield under water stress
situation.
Keywords: Maize, character association, yield prediction, heterosis, genetic studies, heritability
Year: 2003
Volume: 63
Issue: 2
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
Tej Pal Yadav, R.D. Singh and J.S. Bhat info_circle
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