الفهرس 
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Abstract
The first study
The aim of this study was to investigate general and specific
combining ability, heterosis and types of gene action and their
interaction with environments (irrigation treatments i.e. sprinkler
irrigation every 4,8 and 12 days) for plant height, height ofpedunc1e
leaf, grain, straw and biological yields, and some of yield components
as well as protein content, wet and dry gluten percentages and
semolina percentage.
Six parental durum varieties namely; Bani Sweif 1 (PI), Bani
Sweif 2 (P2), Bani Sweif 3 (P3), Sohag 1 (P4), Sohag 2 (Ps) and Sohag
3 (P6), representing wide range of variability in most of the studied
traits, were used. These parental varieties were planted in 1996/1997
season and crossed in half diallel combinations without reciprocal to
obtain seeds of 15 FI hybrids. A half diallel set of crosses involving
six parents were evaluated under three sprinkler irrigation every
treatments namely; 4, 8 and 12 days in three separate experiments,
were used. Three adjacent experiments were conducted, the first,
second and third experiments were sprinkler irrigated every 4, 8 and
12 days, respectively. In each experiment, the parental varieties and
their possible crosses were arranged in a randomized complete block
design with three replications at Ismailia Agricultural Research
Station. Each plot comprised of two rows 2 meters long with 30 cm
between rows. Plants within row were 20 cm apart. The data for each
trait were analyzed on individual plant mean basis. An ordinary
analysis of variance was firstly performed for each sprinkler irrigation
treatment. Combined analysis of the three experiments were carried
out whenever homogeneity of error variance of three sprinkler
irrigation treatments were detected. Heterosis was computed as mean
squares and the percentage deviation of FImean perfonnance from
either the mid- or the better parent mean values for the separate
irrigation treatment as well as the combined data.
General and specific combining ability estimates were obtained by
employing Grilling’s (1956) diallel cross analysis designated as
method II model 1. The obtained results can be summarized as
follows:
1. ’Irrigation mean squares were significant for all the studied
traits. The effect of sprinkler irrigation every 8 days increased
significantly yield and some of its components. While. the
effect of sprinkler irrigation every 4 days had the highest
values for quality characters.
2. Mean squares for genotypes, parental variety and F1 hybrids.
were significant for all studied traits. except parent mean
squares for number of spikes and semolina in the combined
data.
3. The cross P4 X Ps has the highest grain and biological yields
per plant. but without significant superiority over the two
crosses P2 x Ps an P3 x P4 in the combined analysis. The cross
P2 x P3 gave the highest values for dry and wet gluten
percentages in the combined analysis.
4. Mean squares for parents vs. crosses as an indication to
average heterosis overall crosses were significant for all traits
in separate irrigation treatments as well as the combined
analysis except straw yield and semolina percentage at the
combined analysis, biological yield at sprinkler irrigation
every 8 day, and dry gluten % at sprinkler irrigation every 4
and 8 days. F1 means were significantly higher than parental
mean for most traits.
5. The variance associated with general and specific combining
abilities were significant for all studied traits in separate
sprinkler irrigation treatment as well as the combined analysis
except variance of GCA for 1000-kernel weight at sprinkler
irrigation every eight days. Grain yield/plant at three irrigation
treatments as well as the combined, straw yield, semolina and
protein percentages at sprinkler irrigation every four days,
biological yield at sprinkler irrigation every 4 and 12 days,
plant height at sprinkler irrigation every 12, lOOO-kernel
weight at irrigation every 8 and 12 days and wet gluten
percentage in the combined analysis exhibited low GCAiSCA
ratio less than unity. While the magnitude of additive and nonadditive
types of gene action were similar for plant height at
irrigation every 8 days as well as the combined analysis,
number of spikes per plant and straw yield per plant at
sprinkler irrigation every 12 days. On the other hand, high
GCAlSCA ratio, which exceeded than the unity was detected
for other cases.
6. The mean squares of interaction between both types of
combining ability and irrigation treatments were significant for
all studied traits, indicating that both additive and non-additive
types of gene action varied from irrigation treatment to
another.
7. The parent P2 for dry gluten, Ps, Ps and P6 for protein
percentage, and lOOO-kernel weight, P4 for peduncle length,
number of spikes, straw and biological yields, and P, for grain
yield and some of yield components seemed to be the best
general combiners.
8. The most desirable seA effects were detected by crosses P, x
P4 and P, x P
4
for peduncle length, PI x P, for s~ort plant, P0_---------
P, for number of kernels/spike, P, x P6 and P4 x .-7
kernel weight, p\ x P3, p\ X P4, P2 X P4
yield, PI x P4, P2 X P” P4 X P6, Ps X P4, Ps X P6 and P4 x Ps for
grain yield/plant, PI x P4, P2 X Ps and P, x P6 for biological
yield, PI x P” PI X P6, P, X Ps and P4 x P6 for semolina
percentage, P2 x Ps and P, x P6 for dry gluten percentage and
P2 x P3 and P4 x P6 for wet gluten.
The second study
A field experiment was carried out at Bahteen Experimental
Station during 1996/1997 and 199711998 season to study the respouse
of six varieties of T turgidum var. durum and Gemmeiza 3 (T
aestivum) to nitrogen levels for some agronomic and quality
characters. The materials used in this study involved six parents in the
first series (Bani Sweif 1, Bani sweif 2, Bani Sweif 3, Sohag I, Sohag
2 and Sohag 3 as well as Gemmeiza 3 (T. aestivum). The varieties
were fertilized by N levels in the form of Ammonium nitrate (33.5%
N) as follows:
1. 75 kg N/fed (Nl) were applied in three equal doses just before
sowing, first and second irrigations.
2. 75 kg N/fed (N2) were applied in four equal doses, just before
sowing, first, second irrigationand at heading time.
3. 100 kg N/fed (N3) were applied in four equal doses just before
sowing, first, second irrigationsand at heading date.
A split-plot design with four replications was used. The main plots
were randomly assigned to three nitrogen fertilizer levels, while the
six varieties of durnm wheat as well as check variety Gemmeiza 3 (T.
aestivum) represented sub-plots. The results could be summarized as
follows:
A. Growth, yield and its components
1. All studied characters except plant height, peduncle length and
number of kernels/spike were significantly differed from
season to another.
2. Gemmeiza 3 cultivar gave the highest averages of straw
yield/feddan in both seasons.
3. Bani Sweif 2 cultivar had the highest grain yieldlfeddan in
both seasons, whereas both Gemmeiza 3 and Sohag 1 cultivars
had the lowest grain yieldlfeddan in the first and second
season, respectively.
4. The highest average of the biological yieldlfeddan recorded by
Sohag 3 and Gemmeiza 3 cultivars in the first and second
season, respectively.
5. The highest average of straw yieldlfeddan was obtained when
applying N rate in four equal doses up to 75 kg N/feddan in the
first season and up to 100 kg N/feddan in the second season,
respectively.
6. The highest grain yield ardab/feddan was accompanied to N
application level of 75 kg N/feddan when N rate was splitted
into three doses in the first season and four doses in the second
season.
7. The effect of nitrogen levels on grain ardab/feddan, biological
yields (ton/fed) and yield components was changeable from
season to season.
8. The effect of N rate up to 75 kg N/feddan in three doses with
Gemmeiza 3 showed the highest value for straw yield
ton/feddan.
9. The highest values for grain and biological yield ton/feddan
were obtained when N rate up to 75 kg N/feddan in four doses
were applied with Bani Sweif I cultivar.
B. Quality characters
1. Sohag 2 cultivar had the highest semolina, protein and wet
gluten percentages. Whereas, the highest dry gluten percentage
was recorded by Bani Sweif 3 cultivar.
2. The application of N levels in four equal doses up to 7S kg
N/fed and 100 kg N/fed gave significant values of protein and
dry gluten percentages, respectively.
3. The highest mean value of semolina percentage was detected
by adding N rate in three doses up to 7S kg/feddan with Bani
Sweif 2 cultivar.
4. The highest dry gluten percentage was obtained when applying
N rate in four doses up to 75 kg N/fed with Sohag 2 and
Gemmeiza 3 cultivars.
5. The highest wet gluten percentage was obtained by Sohag 1
cultivar given N rate in four doses up to 75 kg N/feddan.
6. Bani Sweif 3 cultivar produced highest concentration of
protein percentage when received N rate in four doses up to
100 kg N/feddan.