A half diallel set of crosses among six inbred lines of sweet corn was evaluated to study heterosis and combining ability among plant height, ear height, ear diameter, number of rows per ear and ear yield per plant. The study was carried out at the a
gricultural research center in, GCSAR, Lattakia, Snoubar Jableh, during the 2010, 2011 seasons.
Result showed that almost all crosses expressed a significant positive heterosis effect for ear yield per plant relative to mid parents and better parents; whereas, the highest positive significant percentage of heterosis for ear yield per plant were expressed by the crosses (L4xL6) which gave (198.70%, 176.81%) and (L4xL6) which gave (196.94%, 168.56%), over mid parents and better parents, respectively.
The ratio (σ2GCA/σ2SCA) which was less than (1) showed that the non-additive gene action was more important than the additive gene action in all traits except plant height and ear height. The inbred lines L3 (17.061) and L4 (12.011) seemed to be the best general combiners for ear yield. Also, based on SCA effects, many of single crosses were identified as superior for ear yield, and the best hybrid was L3xL5(50.173).
A half diallel set of crosses among six inbred lines of maize were evaluated at the
Maize Research Department (G.C.S.A.R.) in Damascus Governorate during 2010 and 2011
growing seasons to estimate heterosis and combining ability components for the n
umber of
rows per ear, number of kernels per ear, ear length (cm), ear diameter(cm), 100-kernel
weight (g), and grain yield (ton /hec).
The inbred lines, crosses, general combining ability (GCA) and specific combining
ability (SCA) mean squares were highly significant for all the studied traits, showing the
existence of a genetic variance among lines.
The ratios of GCA to SCA detected for the studied traits showed the dominance of an
additive gene action for all the studied traits except for 100-kernel weight and grain yield
which showed the predominance of a non-additive gene action.
The heterosis percentage for the studied traits was significant based on mid and
better parents.
The GCA effects showed that the lines CML.317, CML.371, CML.373 and
CML.367 were good general combiners for grain yield, while the SCA effects showed that
seven hybrids were the best F1 cross combinations such as (CML.317×CML.371) for grain
yield.
Eight varieties of soft wheat T.aestivum L. were used in the study, four of which
were local (sham 6, sham 8, sham 10 and bohoth 4) and four introduced varieties obtained
from the Scientific Agricultural Research Center (Tugela, Betta, Bezenchukska
ya98 and
saratovskaya210) and grown during the periods (2011-2012 and 2012-2013) at Qabu Al
Awwamiyya near Lattakia City. The following readings were taken for the studied
varieties (yield, plant height, spike length, number of spikelets per spike, weight of 1000
grains, protein content proportion of gluten, ash, and moisture content). Data was analyzed
statistically using an analysis of variance. The results showed significant differences
between the local and introduced varieties on the one hand, and between the varieties
themselves on the other hand. Local varieties were better than the introduced varieties with
regards to the protein content, moisture content, proportion of gluten, yield, spike length,
number of spikelets per spike, and the 1000-grain weight. The introduced varieties
however were superior in plant height and ash. The best varieties among local varieties
were (Sham 6 and Sham 10), and Betta among the introduced ones.
Five populations of faba bean were advanced from F2 to F3 generations by simple
recurrent selection at Terbol research station, International Centre for Agricultural
Research in The Dry Areas (ICARDA), Lebanon. During the growing season summer
201
3. The produced genotypes of selection were evaluated in winter 2013-2014 in order to
estimate the narrow-sense heritability and genetic advance for seed yield, plant height,
pods per plant and 100-seeds weight traits. The results showed that S2012-085 population
was superior in heritability for seed yield (0.5), 100-seed weight (0.5) and pods per plant
(0.5), while the population S2012-133 was recorded the supreme value for plant height
(0.858). The results demonstrate that genetic advance for seed yield trait was varied from
53% to 72.4%, and the highest value of genetic advance for seed yield was belonged to the
population S2012-018 (72.4%). Most of traits under research were recorded a moderate
values of narrow sense heritability accompanied with high values of genetic advance,
indicating to the importance of additive genetic variances related to the total genetic
variances, Consequently, recurrent selection is very important to apply in order to improve
the traits across segregated generations of faba bean.
This study was carried out during 2010-2011 growing seasons at the
Maize Researches Department (G.C.S.A.R.) Damascus. To estimate
heterosis for number of rows per ear, ear length, ear diameter, 100- kernel
weight, and grain yield.
Eleven genotypes of Bread Wheat (Triticum aestivum L.) were tested at three diverse
locations in the Syrian Coast during the 2015-2016 season under rain-fed conditions to
assess these genotypes and to study the Genotypes x Environments Interactions
, and yield
stability across environments using 5 statistical measures of stability:{ X¯i, bi, and i
according to Eberhart and Russell (1966), Stability Variance Index (2
i) according to
Wricke and Weber (1980), Ecovalance Stability Index (Wi) according to Wricke (1962)}.
Genetic material included 5 promising lines and 6 local varieties (provided by ACSAD and
GCSAR).The experiment was designed using randomized complete block design with
three replications, statistical data analysis was done, and least significant difference
(L.S.D) test at 5% was applied for comparison of means. Significant differences were
observed among bread wheat genotypes for grain yield (ton/ha), combined analysis of
variance of grain yield across the three environments showed significant mean squares due
to genotypes, environments and genotypes x environments interaction, suggesting
differential responses of genotypes across studied environments and validity of stability
analysis.
Stability analysis for grain yield revealed that; the promising line ACSAD-1147 and
Doma6 were more stable than other genotypes. Due to they had superior ranks for both
average yield over environments and yield stability, which reveals the importance of these
genotypes to reach varieties that combine relatively high yield and better stability in any
future breeding programs.