الفهرس 
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Abstract
Summary and conclusion
The region of El Wadi El Gadeed governorate represents about
45% of total area of Egypt however the cultivated area isn’t exceeded
3%. The aim of this work was to increase wheat cultivars (Sids1,
Gimmeza7) tolerance to heat stress by using synthesized nanoparticles.
Four biocompatible nanoparticles were prepared successfully
(Cu NPs <50 nm, Zn NPs <100nm, Fe NPs <50 nm and conjugation
between SA + Fe NPs) from cheap sources. All these NPs had an
effective role on enhancing wheat tolerance to heat stress of both
cultivars. Our results indicated that:
1. Growth traits
-Copper NPs (1.0 ppm) showed a positive effect on most plant
growth traits except fresh and dry weights of 2nd growth stage when
compared to the control.
-Besides, Zn NPs and Fe NPs treatment showed the same
positive effect on most growth traits at both growth stages especially at
0.25 ppm when compared to the control.
-Concerning, Fe NPs, Sids1 exceeded Gimmeza7 in fresh
weight at both growth stage but, at 2nd growth stage Sids1 exceeded
Gimmeza7 at dry weight. In addition, SA+Fe NPs had a negative effect
on plant height. The lowest mean value was recorded by 10ppm at both
growth stages but, had positive effect at the other parameters.
Gimmeza7 exceeded Sids1 at plant height at 1st growth stage.
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2. Biochemical markers:
a.Malondialdehyde content
-Copper NPs metal treatment decreased MDA content at both
growth stages of wheat plants under heat stress conditions i.e.; the
lowest mean value was recorded at Cu NPs 1.0 ppm at 1st growth stage
and 0.50 ppm at 2nd growth stage. Gimmeza7 had the lowest mean
record at 1st growth stage than Sids1.
-In Zn NPs treatment, the lowest mean value of toxic product
was achieved by Zn NPs 0.75 ppm at both growth stages. Gimmeza7
recorded the lesser amount of MDA than Sids1 at both growth stages.
-Fe NPs showed a negative effect on MDA content but the
lowest mean value of lipid peroxidation product was obtained by Fe
NPs 0.50 ppm at 1st growth stage but at 2nd growth stage the lowest
value was obtained by 10 ppm. Gimmeza7 was the lowest in MDA
content than Sids1 at only 1st growth stage.
-Conjugated SA showed negative effects on MDA content. The
minimum mean value of lipid peroxidation product was recorded by 1.0
ppm at 1st growth stage and 0.25 ppm at 2nd growth stage. Gimmeza7
had the lowest mean values of lipid peroxidation product and cell
membrane damage than Sids1 at 1st growth stage.
b.Glutathione reduced content
-Copper NPs had a positive effect on it and the most effective
dose was Cu NPs 1.0 ppm at 1st growth stage and 10 ppm at 2nd growth
stage. The highest mean value was recorded by Gimmeza7 rather than
Sids1 at 1st growth stage.
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230
-Zinc NPs showed positive effect on increasing in GSH level on
both stages, in this connection it is clear that, the highest mean value of
GSH was detected at 0.75 ppm Zn NPs at 1st growth stage but at 1.0
ppm Zn NPs at 2nd growth stage. Gimmeza7 exceeded Sids1 at 1st
growth stage in GSH level but the opposite was occurred by Sids1 at
2nd growth stage.
-Iron NPs showed a marked increase on GSH level at both
growth stages but the maximum mean value was at 0.50 ppm at 1st
growth stage and 1.0 ppm at 2nd growth stage.
-Iron NPs conjugated with salicylic acid showed enhancing
effect on GSH level of wheat plants under heat stress conditions. The
highest mean value of GSH was recorded at 0.50 ppm at 1st growth
stage and 0.75 ppm at 2nd growth stage. Sids1 exceeded Gimmeza7 in
GSH content at both growth stages.
c.Glutathione -S- Transferase activity
-Copper NPs application increased GST activity when
compared with the control. The maximum activity was recorded at Cu
NPs 1.0 ppm at both growth stages. Gimmeza7 had the higher activity
of GST at 2nd growth stage.
-Zinc NPs enhanced the activity of GST when compared with
the control at 0.75 ppm and 1.0 ppm at 1st and 2nd growth stages
respectively.
-Iron NPs enhanced GST activity on both growth stages but the
maximum activity was at 1.0 ppm and 0.25 ppm at 1st and 2nd growth
stages respectively.
-Magnetite with SA increased GST activity especially at 0.25
ppm at both growth stages. Sids1 exceeded Gimmeza7 at 1st growth
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231
stage in GST activity. However, the reverse took place at 2nd growth
stage.
d. Peroxidase
All NPs Cu, Zn, Fe and SA+Fe had positive effect on POD
isoforms under heat stress conditions where both cultivars had 5
isozymes from POD.
There is variation on appearance and disappearance of bands, in
this direction, band number 3 is present at both cultivars and control
except for Gimmeza7. Most NPs treatments increased band intensities
when compared to the control and highest band intensity was at Zn NPs
(0.75 and 1.0 ppm), Fe NPs (0.50 ppm) finally, (0.25 ppm SA+Fe NPs).
e. Superoxide dismutase
SOD isozymes where Sids1 bands were about 7 bands and the
same was represented by Gimmeza7. Regarding Sids1 cultivar, the
major band was band number 1, 2, 4 and 7th one which were present at
all treatments of NPs and control. Band number 3 was unique at
(SA+Fe NPs, 10 ppm) and absent from all treatments and control.
f. Catalase
CAT isozymes’ data obviously showed the effect of NPs
treatments on Sids1 and Gimmeza7 cultivars’ CAT isozymic behavior
under heat stress conditions. There was variation in effect of NPs
between appearance and disappearance of some isozyme bands.
Through this, Sids1 and Gimmeza7 had 8 bands.
The appearance of unique bands on the newly synthesized
bands may be due to protein destruction or in relation with NPs
treatments to counteract heat stress.
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232
g. Heat shock proteins
-The protein analysis was at SDS-PAGE 10% that there were
about 17 bands ranged from (228.0 to 19.0 kDa) for Sids1 cultivar.
from data and the electrophoregram, the polypeptide 228.0 kDa was
present at all NPs treatments and control. However, Cu NPs and Zn
NPs increased the biosynthesis of this polypeptide when treated with
0.25ppm from both mentioned NPs. Other treatments also increased its
biosynthesis and accumulation at (Fe NPs, 10ppm) and (SA+ Fe NPs,
0.75ppm).
-The polypeptide 20.00 kDa was present only at control, Cu
NPs (0.25ppm), Zn NPs (0.25 and 0.75 ppm) and SA+ Fe NPs (10ppm)
but disappeared from the other NPs treatments. A unique polypeptide
with molecular weight 19.00 kDa was only accumulated at SA+ Fe NPs
(10ppm) but eliminated from control and other NPs treatments.
-Concerning Gimmeza7 cultivar, there was a complete
destruction to polypeptides due to the NPs effect.
h. Genetic invariability of DNA
from the overall data shown in tables and figures, it is reported
that, there were a detected variations between appearance of new AFs
and elimination of others besides stability of most of them. These
results reflect some unwanted effects of some doses of NPs.
i. Yield
Minerals content
-Copper NPs had a positive effect on macro and micro elements
of Sids1 grains, the highest record of Ca, Ni and Si was reported by Cu
NPs 1.0 ppm. The maximum values of Fe, Zn and Cu were achieved by
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233
Cu NPs 0.50 ppm when compared to the control. Zn NPs with all
concentrations had positive effect on all measured parameters of
minerals of Sids1 grains. In addition, Fe NPs increased Ca content
especially at 0.50ppm. The SA+Fe NPs had negative effect on Ca, Cu
and Si content.
-Copper NPs had positive effect on most elements level in
Gimmeza7 cultivar but highest record was achieved by Cu NPs (0.50
ppm) for Ca, Ni, Fe, Cu and Si. Moreover, Zn NPs had a positive
effect on minerals level of Gimmeza7 cultivar especially at Zn NPs
(0.75ppm). Noteworthy, Fe NPs had positive effect on some
minerals.i.e, the highest value of Ca, Mg, Mn, Zn, Cu and Mo was
detected at Fe NPs 0.50 ppm. Fe NPs also had a negative effect on both
Ni and Fe of Gimmeza7 cultivar. The SA+Fe NPs showed a positive
effect on most of the minerals but the highest value of Ca, Ni, Fe, Zn,
Cu and Si was recorded at 0.50 ppm of conjugation.
Amino acids content
-In Sids1, Cu NPs decreased the biosynthesis of essential and
non-essential amino acids i.e, increased their degradation except for
Cu NPs 0.25 ppm enhanced accumulation of all essential and nonessential
amino acids when compared to the control.
-Zn NPs and Fe NPs had positive effect on most of essential
and non-essential amino acids in grains. The highest records of
essential and non-essential amino acids were reported by Zn NPs and
Fe NPs 0.75 ppm.
-SA+ Fe NPs showed variable effect on biosynthesis of amino
acids in Sids1 cultivar. Regarding the positive role of this composite it
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234
was clear that, maximum value of essential amino acids was obtained
by composite at 0.50 ppm.
-Regarding Gimmeza7 cultivar, Cu NPs had destructive effect
on most essential and non-essential amino acids in grains with all doses
of such NPs. However, .Zn NPs had positive role in Gimmeza7 plants’
grains. Highest value of essential and non-essential amino acids was
recorded at Zn NPs 1.0 ppm. Fe NPs showed a marked decrease of both
essential and non-essential amino acids when compared to the control.
-SA+ Fe NPs showed a positive effect on most of essential and
non-essential amino acids, especially at concentration 0.50ppm.
Yield traits
-Cu NPs treatment enhanced yield and its parameters, the
highest mean value of plant height and grain yield was recorded at Cu
NPs 1.0 ppm. Sids1 surpassed Gimmeza7 at only grain yield but there
was no significant difference between both cultivars at the remnant
parameters of yield.
-Zinc NPs showed marked increases in all yield parameters
however, the highest mean value of plant height was detected by Zn
NPs 0.25 ppm, grain yield (0.75 ppm) when compared to the control.
Gimmeza7 exceeded Sids1 at grain yield.
-Moreover, Fe NPs also showed a positive effect on all yield
parameters in the light of this statement, the maximum of plant height
and grain yield was at 0.25 ppm.
- SA+ Fe NPs had a positive effect on all yield parameters, the
maximum mean value of plant height and grain yield was at 0.50 ppm.
It is well known that, Gimmeza7 surpassed Sids1 at grain yield.
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235
3. TEM microscopy
from the overall results and micrographs, it is obvious that the
effect of several above mentioned NPs was varied according to cultivar,
type of element and dosimetry dependent.
There were some positive change in the organelles of plant cell
like, starch granules became enlarged, appearance of vacuolation
process due to increased storage to plant nutrients when plants exposed
to stress , and lignification of cell wall as a defense mechanism