الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This study was carried out at the Experimental Station of
Desert Research Centre in Wadi-Sudr- South Sinai through three
successive seasons; 1993/1994, 1994/1995 and 1995/1996.
The study includes treating grains of two cultivars of wheat
and barley with two mutagens, one of them was irradiation (Gamma
rays) and the” other was chemical mutagen (ethylene imine). The
grains of the two cultivars (Sakha 92 of hexaploid wheat and Giza
123 of six-rowed barley) are treated with doses of gamma rays; 10,
20 and 30 Krad. While the other part of grains of the two varieties
treated with three concentrations of ethylene imine; 0.15 %, 0.30 %
and 0.45 %.
Percentage of grain germination of both treated cultivars was
count in lab since grain were exposed to water with 6500 p.p.m of
sodium chloride.
Grains were grown in complete randomized block design
experiment for the wheat and barley cultivars for each mutagen in
soil irrigated. with under-ground saline water (nearly 6500 to 7000
p.p.m.) Data were obtained on the M) plants, M2 and selected
mutants from the grains ofM3•
The study was classified into four main parts:
1. Salinity effect on the germination.
2. The mutagenic effect on the morphological and yield component
characters under saline conditions.
3. Cytological-studies:-
3.a. Cytological behaviour of chromosomes in mitosis.
3.b. Cytological behaviour of chromosomes in meiosis.
4. The DNA quantity during interphase.
L Salinity effect on the germination percentage of wheat
and harley grain cultivars:
The results showed that decreased _at the percentage in
untreated grains. While it was highly decreased in wheat more than
barley. Bath mutagens (gamma rays and ethylene imine) cused
highly decreases in germination percentage in while, ethylene imine
was more effective on germination percentage particularly in barley
under 0.30 and 0.45%
IL The mutagenic effect on the morphological characters
and grain yield under saline conditions in Ml and M2.
The mean values induced after gamma rays or ethylene imine
treatments for wheat (Sakha92) and barley (Giza123) in different
quantitive characters; plant height, no. of spikes per plant, no. of
spikelets per spike, no. of grains per spike, 1000 grain weight and
grain yield per main spike were recorded in Ml and M2 generations.
In the case of wheat (Sakha92) the mean of plant height in M,
generation was significantly reduced at all doses (10,20 and 30
Krad) of gamma rays but it was highly significant increased at all
concentrations (0.15%, 0.30% and 0.45%) of ethylene imine. While
significant increases in the mean values of plant height were
observed after both gamma irradiation or ethylene imine treatment in
M2 generation. Phenotypic, genotypic variances, genetic coefficient
variation and heretability were increased after treatment with two
mutagens but ethylene imine was more effect than gamma rays. The
mean of no. of spike per plant in Ml generation was significantly
decreased at all doses of gamma irradiation but it was highly
significant increased at all concentrations of ethylene imine. While
in M2 generation it was highly significant increased after all
treatments of both gamma rays and ethylene imine. Calculation of
genetic coefficient of variation indicated that the amount of genetic
variances after ethylene imine. Hence, estimation of heretability after
treatment with gamma rays generally resulted in high values than
that obtained after ethylene imine treatment. The main of no. of
spikelets per spike in Ml generation was significant and highly
significant reduction at doses 20 and 30 Krad and it was
insignificantly at 10 Krad, dose of gamma rays but it was slight
reduction at 0.15% and slight increased at 0.30% and 0.45%
concentration of ethylene imine. While significant increases were
observed in M2 generation after both gamma rays and ethylene
imine treatments. It is worth to note that this increment after gamma
irradiation was more than that ethylene imine treatment. Estimated
values of genetic coefficient of variation were lower after two doses
(10 and 20 Krad) of gamma rays than ethylene imine. Accordingly,
low heretability estimates were detected especially after 10 and 20
Krad of gamma rays as well as 0.45% concentration of ethylene
imine. The mean of no. of grains per spike in MI generation was
slight decrease at dose 10 Krad of gamma rays and at 0.15% and
0.30% concentrations of ethylene imine, but it was highly significant
reduction at both of 30 Krad of gamma rays and at 0.45%
concentration of-ethylene imine. While in M2 generation significant
increment and with lowest genotypic variance, genetic coefficient of
variation and heretability were detected after tow doses (10 and 20
Krad) of gamma rays but insignificant differences were detected of it
after ethylene imine treatments. The mean of 1000 grain weight in
Ml generation was highly significant reduction at doses 20 and 30
Krad and it was slight and not significant at 10 Krad of gamma rays
it was highly significant reduction at all concentrations of ethylene
imine. While in M2 generation it was highly significant decreases
after all treatment by both gamma rays and ethylene imine. Both
phenotypic and genotypic variances were increased proportionally as
gamma rays doses increased, meanwhile 0.15% concentration of
ethylene imine gave more variability than 0.30% and 0.45%
concentration. High percentages of hertability were detected at all
treatments. The mam of grin yield per main spike in the M1
generation was slight reduction at 10 Krad. But it was highly
differences at 20 and 30 Krad while it was highly differences at all
concentrations of ethylene imine. Meanwhile in the M2 generation
with three doses and concentrations of both gamma rays and
ethylene imine, there were inconstant mean performance significant
decreases at 10Krad of gamma rays and 0.45% concentration of
ethylene imine and it was highly significant decrease at 30 K.rad of
gamma rays. For all other genetic parameters, they were increased
proportionally as dose of each treatment increased.
In the case of barley (Giza 123), the mean of plant height in
the Ml generation was significantlyreduced at 30 Krad and highly
significant increase at 10 Krad. But it was slightly reduced at all
concentrations of ethylene imine, while in the M2 generation it is
clear that· ethylene imine treatments were more effective in
increasing the plant height than gamma irradiation. The mean of no.
of spikes per plant in the M2 generation was significantly decreased
after 10 and 20 Krad doses of gamma rays and it was highly
significant increase after 0.15% concentration of ethylene imine. The
dose 20 Krad of gamma rays gave the highest genetic coefficient of
variations and high percentage of heretability. The mean of no. of
spikeletes per spike in M1 generation was increased at 10 and 20
Krad and it was decreased non-significantly at 30 Krad of gamma
rays. While in the M2 generation it was highly significant increment
were proportionally accured after ethylene imine concentration
treatments increased as well as at 30 Krad of gamma rays. Both
mutagens caused as increased in genetic coefficient of variation. The
mean of no. of grains per spike, in M1 generation it was highly
significant increase at 10 and 20 Krad doses and slight decreased at
30 Krad of gamma rays but it was significant decrease at 0.30% and
it was insignificant decreased at the other concentrations of ethylene
imine, while in the M2 generation it was significantly reduced after
irradiated with 10 Krad dose of gamma rays. However, ethylene
imine treatments were found to increase the mean of this trait more
effectively than did the higher dose (30 Krad) of gamma rays. the
highest genotypic variance were accounted after 20 and 30 Krad
doses. The. mean of 1000 grin weight in M] generation was a slight
reduction at 20 Krad and it was highly significant decrease at 30
K.rad of gamma rays and at all concentrations (0.15%, 0.30% and
0.45%) of ethylene imine. While in the M2 generation it was
significant reduction after treatment with both of gamma rays and
ethylene imine, however 10 and 20 Krad doses of gamma rays were
more effective then all concentrations of ethylene imine. The mean
of spike yield in M) generation was slight reduction at 20 Krad and it
was increased significantly at 10 Krad but it was insignificant
decrease at 30 Krad dose of gamma rays. While it was slight
Increases at 0.15% and 0.30% and it was found a significant
reduction at 0.45% concentration of ethylene imine. Meanwhile in
M2 generation highly significant increasing of yielding ability was
detected after ethylene imine treatments. Both mutagens caused an
increase in genetic coefficient variation. Heretability estimates were
increasing at 20 and 30 Krad doses of gamma rays.
from the M2 generation,mutants were selected and grown to
arise the M3 generation. Data described the morphological and yield
characters of these mutants as a result to irradiation with gamma rays
and ethylene imine treatments of both wheat (Sakha92) and barley
(Giza123) culivars.
The macromutant types in wheat at both of gamma rays and
ethylene imine treatments was comprised three mutations viz. No. of
spikes per plant, 1000 kernel weight and spike yield per main spike.
While in the case of barley (Giza123), the macromutant types at both
of gamma rays and ethylene imine treatments comprised six
mutations viz. plant height, no. of spikes per plant, no. of spikelets
per spike, no. of” grains per spike, 1000 kernel weight and grain
yield per main spike.
The high frequency of each mutant type was relatively higher
when using both of two mutagens with barley (Giza 123)
III. CytologicalStudies
The results showed that both mutagens (gamma rays and
ethylene imine) caused an increase in somatic or PMC’s cells, while
the effective of gamma rays is significantly higher than ethylene
imine. Moreover, the quantities of chromosomal aberration.
IV. The DNA quantity during interphases:
from the results, the increasing of gamma rays doses on the
percentage of cells DNA synthesis more effect in barley than wheat.
Mean while, the increasing of ethylene imine concentrations increase
the percentage of non divided cells and decrease the percentage of
DNA synthesis cell sharply in wheat. On the other hand, in barley
the increasing of ethylene imine concentrations increase gradually
the percentage of non divided cells and decrease gradually the
percentage of DNA synthesis cells compared with the control.
Generally, the data indicated that, gamma ray doses more
effect on wheat than barley. While ethylene imine more effect on
barley than wheat.