الفهرس 
Effect of Salinity on Plant PhysiologyOnly 14 pages are availabe for public view
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Abstract
The present study was carried out to evaluate the impact of
irrigation with two different concentrations of seawater; (50 mM)
and (150 mM) (as a source of salinity stress) and (125 mM) of
mannitol as osmoprotectant on some physiological and
phytochemical parameters of Anastatica hierochuntica . plant
(Kaff maryum). Also to improve plant performance and
production of phytochemicals, in particular flavonoids.
1- Physiological results
Percentages of germination
The present results showed that there is a negative
correlation between the concentrations of seawater and the
percentage of germination as being compared to the control
Also, such reduction in percentage of germination is recorded in
case of mannitol alone and mannitol in combination with
salinity.
Growth at the vegetative stage
There are significant decreases in the shoot length for all
treatments except the low concentration of salinity (50 mM)
which gives significant increase as being compared to the control In addition, mannitol alone induced a significant reduction in
shoot length and non significant reductions in combination with
both low and high salinity concentrations (MS1 and MS2). In
contrast, the root length showed significant increments in
response to both salinity treatments (50 mM and150 mM). Both
salinity concentrations (50 and 150 mM) increased the fresh and
dry weights of A. hierochuntica . In contrast, mannitol alone
and in combination with (150 mM) reduced both the fresh and
dry weights respectively.
It is obvious that there is a positive correlation between the
number of branches and leaves number and this correlation is
concurrent with increase in the leaf area in response to both the
low and high concentrations of seawater as compared to the
control. In addition, mannitol interaction with the low saline
solution (50 mM) showed no change in both the branches
number and leaves number, while the leaf area was reduced as
being compared to the control.
Growth at the yield stage
It is obvious from the results that only S1 treatment (50
mM) saline solution induced shoot length as being compared to
the control. Both the low and high concentrations of saline
solution had stimulatory effect on the root length, while mannitol alone or in combination with the high concentrations (150 mM)
had inhibitory effects. Application of saline solution at the low
and high concentrations (50 and 150 mM) induced significant
increments in both the fresh and dry weights of A. hierochuntica
plants. Mannitol in combination with (150 mM) significantly
reduced the fresh weight and non siginificantly reduced the dry
weight.
Regarding the number of branches and fruits per plants, it
is evident that the number of branches A. hierochuntica
increased in response to both salinity treatments alone (50 mM
and 150 mM) or in combination with mannitol (MS1 and MS2)
and this was concurrently followed by increments in the number
of fruits per plant. In contrast, mannitol treatment alone
decreased both the number of branches and fruits per plant.
Changes in metabolites
Changes in photosynthetic pigment
The results showed significant increments in chlorophyll a
,chlorophyll b and carotenoids in response to the treatment with
the low concentration of seawater alone (50 mM) or in
combination with mannitol as being compared to the control .
Concerning the higher concentration of seawater (150 mM), itshowed two different trends for being alone or in combination
with mannitol.
Changes in carbohydrate contents
The results showed significant increments in all sugar
contents in response to the treatment with the lower
concentration of seawater alone (50 mM) or in combination to
mannitol as being compared to the control. The high
concentration (150 mM) accumulated the highest amount of
polysaccharides in the shoot system.
Changes in Antioxidant Compounds
Proline showed high significant increments in all treatments as
being compared to the control. The lowest proline content was
under mannitol.
Anthocyanin contents were significantly increased under both
seawater and/or mannitol treatments, the control plants have the
least amount than all treatments.
Vitamin E content
It is clearly shown that irrigation with (50 mM) of seawater
either alone or in combination with mannitol had significant
increases. On the other hand, the higher concentration (150 mM)
decreased vitamin E content.Total phenolic
Concerning the total phenol contents, it is clearly shown
that all treatments significantly increased these contents as being
compared to the control. It is noticeable that the total phenolics
contents increased by increasing the concentration from the lower
concentration (50 mM) to the higher one (150 mM), Also the
above contents showed the highest values at mannitol interaction
with both the concentrations especially the high one (150 mM).It
is also clear that the vegetative stage is more rich in the phenolic
contents than the yield stage.
Total flavonoids
The total flavonoid contents mostly showed the same pattern
as that of total phenolics, it is also important to mention here that
there is a strong positive correlation between the total phenolices
and total falvonoids contents. Moreover, the accumulation of
flavonoid compounds was attributed to an increase in the level of
the major compounds; kaempferol 3-O-β-glucopyranoside,
quercetin and quercetin 3-O-β-glucopyranoside.
Antioxidant activity
It is evident from the antioxidant activity increased by
increasing the total phenolics and flavonoid contents.Changes in the protein profile
There are some qualitative changes which include the
disappearance and appearance of de novo synthesized bands.
The disappeared bands are 114 kDa in mannitol interaction with
both 50 mM and 150 mM and 37 kDa in S2 and M .Six de novo
synthesized bands are 97 kDa, 64 kDa, 40 kDa, 33 kDa, 22 kDa
and 14 kDa. but 97 kDa appeared in MS2 only, 64k Da in MS1,
40k Da in all treatments, 33 kDa in S1 and S2, 22 kDa in M only
and finally 14kDa in all treatments.
2-Phytochemical analysis
Quantitative estimation of flavonoids at the vegetative stage
It is clearly shown from the present work that twelve
flavnoid compounds were separated from A. heriochuntica. in
relation to the effect of seawater, mannitol and their interaction.
All treatments had great amounts of the separated flavonids as
being compared to the control. Moreover, the increase in levels
of these three compounde reflected the change in total phenolic
content and flavonoid compounds. they were Kaempeferol 3-O-
-rutinoside, Quercetin, and Quercetin 3-O--glucopyranoside.
Five Compounds were isolated for the first time from A.
hierochuntica. The extracts of control C, include flavonoids (1-12) and the five treatments (S1, S2, M, MS1 and MS2) were
subjected to HPLC analysis as well as CO-PC with authentic
samples using two dimension paper chromatography (2D-PC).
Twelve flavonoid compounds were isolated and identified
from the control extract of A. hierochuntica (vegetative
stage).They were identified as apigenin (1), luteolin 7-O-β-
glucopyranoside (2), luteolin 7-O--glucronoide (3), kaempferol
3-O-β-glucopyranoside(4),quercetin (5), quercetin 3-O-β-
glucopyranoside(6), quercetin 3-O-rutinoside (Rutin) (7),
apigenin 6-C--glucopyranoside [isovitexin] (8), apigenin 6C-α-
arabinopyranoside8-C--glucopyranoside (9), luteolin 6-C--
glucopyranoside [isoorientin] (10), luteolin 8-C--
glucopyranoside [orientin] (11) and naringenin(12).
In conclusion, the results of the thesis in hands demonstrated
that the present treatments may signify an effective tool to
induce the phenolic contents, flavonoid compounds as well as
the antioxidant activity of Kaff maryum. The highest yield of
previous metabolites was obtained after two months of
cultivation; therefore, the harvest of the plant is recommended
in the vegetative stage.