Triticeae Genomics and Genetics 2016, Vol.7, No.02, 1
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tolerance of glycophytes differed greatly not only
among species and cultivars, but also among the
different organ of the same cultivar, for example:
In cv. Sakha 94 while, stems, leaves and spikes
enhanced by lower and moderate salinization levels.
Roots reduced by about 38% beyond 150 mMNaCl at
300 mM. In cv. Gimiza 11, while roots reduced by
50% and stem reduced by 25%, leaves reduced about
30% and only 20% in spike at 300mM NaCl.However,
in cv. Gimiza 10 and cv. Giza 168, the reduction in the
four plant organs (stem, leaf, root, and spike) seemly
to be more or less comparable and appeared earlier (at
the lower salinization level). It is worthy to note that
lower concentrations of NaCl stimulated the growth of
wheat shoot and broad bean root and cotton shoot and
root plants (Hamdia and Shaddad, 2014). Abdul
Qados (2011) investigated the effect of sodium
chloride (NaCl) concentrations on growth, of (Vicia
faba L.) seedlings. NaCl caused an increase in plant
height with low and medium concentrations and a
decrease with the highest concentration, in both
measurement periods. No significant effect was
observed in the number of leaves or leaf area with low
concentration, while a decrease was noticed for each,
with two higher concentrations and in both
measurement periods. The inhibitory effect of salinity
of growth as in cv. Gimiza 10 and cv. Giza 168 may
be attributed to the effects of salinity on several facets
of plant activities such as enzyme activity (Seckin
et
al
., 2009), DNA, RNA, protein synthesis
(Anuradhaand Rao, 2001) and mitosis (Tabur and
Demir, 2010). However, plant species differ in their
sensitivity or tolerance to salt stress (Ashraf and
Harris, 2004; Roy et al., 2014), osmotic adjustment
Hamdia and El-Komy (1998), hormonal balance
(Jackson, 1997; Debez
et al
., 2001; Iqbal and Ashraf
(2013) and photosynthesis (Amuthavalli and
Sivasankaramoorthy 2012). The great differences in
the accumulation of carbohydrates among of the four
wheat cultivars and even in their plant organs could
use as a suitable trait for the differences in the gene
expression (Hamdia and Shaddad 1996, Hamdia and
Azooz, 2002 and Balibrea
et al
., 1997). They stated
that the sugar accumulation and its distribution in
different parts of plants could be a valid trait to
discriminate cultivars of different tolerant to saline
and osmotic stress. In some cases the soluble fraction
increased highly significantly which could share in
osmotic pressure, for example leaves of cv. Sakha 94
and to some extent cv. Gimiza 11 accumulated a
suitable amount of soluble sugars in increasing the
osmotic pressure of leaves which could play a pivotal
roles which could achieved water flow from the down
ward into upward, this strategy considered important
in the field of the salt tolerance in the glycophytes.
Plants accumulated the soluble component in leaf to
pooling water from the down ward into upward. On
the other hand and interestingly the most sensitive
cultivars cv. Giza168 and cv. Gimiza 10 failed to
accumulate the soluble sugars in their leaves, this
component dropped markedly beyond 150 mMNaCl,
which might a suitable sign for the great susceptibility
(please again see the observable reduction in the crop
yield of this cultivar).Reduction in plant biomass is
sometimes observed under sever salt stress, and this is
possibly because of the decrease in carbohydrate
accumulation caused by reduction in carbon
assimilation ( Pattanagul and Thitisaksakul, 2008).
Protein contents were also varied among the four
wheat cultivars and their plant organs. It is worthy to
mention that wheat cultivar Sakha 94 maintained,
there is a huge accumulation in the soluble protein in
roots, stems, leaves and spikes whatever the salinity
level used (as in the case of soluble carbohydrates).In
cv. Gimiza 11 the soluble protein induced highly
significantly in leaves, roots and in stems up to 50
mMNaCl, while in spikes soluble protein contents
remained more or less unchanged up to 150 mMNaCl
and
accumulated
highly
significantly
and
progressively at 300 mMNaCl, which indicated also
that the four plant organs responded differently to the
soluble fraction under the salt stress conditions. In
Gimiza 10 also this cultivar failed to accumulate the
soluble protein especially under moderate and higher
salinization levels.
In cv. Giza 168 the most sensitive cultivar also in most
cases failed to accumulate a suitable amount of
soluble protein especially in the principle plant organ
(roots, stems, and leaves). Shaddad
et al
. (2006) and
Chen
et al
., (2007) stated that the accumulation of
soluble proteins helps in triggering and transition of
cells from a state of active growth to a state of salinity
tolerance. The accumulation of compatible solutes is
often regarded as a basic strategy for the production
and survival of plants under salinity stress and
