Triticeae Genomics and Genetics 2016, Vol.7, No.02, 1
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unchanged up to 150 mMNaCl, there after a highly
significant accumulation was recorded at 300mMNaCl.
Also the percent of increase at 300 mMNaCl was 29%.
In spikes proline content enhanced slightly up to 50
mMNaCl, and then it accumulated progressively. The
highest accumulation was reported at 300 mMNaCl
which approached 47% than that in control plants.
The data in figure 3 illustrated a marked variation in
proline content in the four plant organs of wheat
cultivar Gimiza 11. In roots, there is a great reduction
in proline content up to 150 mM NaCl, the magnitude
of this reduction was the highest at the lowest
concentration of NaCl, then it remained unchanged up
to 150 mM NaCl, then a quick and sharp
accumulation was reported at 300 mM NaCl. At this
level the percent of increase in the proline content was
about 130.7% in relation to the control values. In
stems, the amount of proline reduced marginally up to
150 mM NaCl then some promotion was exhibited at
300 mM NaCl (about 21.4% over control values). In
leaves tended in most cases to kept proline content
around the control values whatever the salinity levels
used. In spikes, there is a great and fast accumulation
in proline content at the all salinity levels. The highest
accumulation was recorded at 300 mM NaCl (about
121.4% over the control values).
In roots and stems of cv. Gimizia 10 proline content
dropped progressively whatever the salinity level used.
Interestingly the highest reduction was recorded in
plants irrigated with 150 mM NaCl in both plant
organs. At this level the percent of reduction of proline
in roots and stems was 51.5% and 68.5% respectively,
which considered unexpected results in the
accumulation of proline under stress condition
especially when we take into consideration, that this
cultivar was categorized as a salt sensitive cultivar. In
leaves proline content remained more or less
unchanged up to 50 mMNaCl, and then some
reduction was exhibited. In Spikes proline content
dropped quickly, it dropped by about 57% at 300
mMNaCl respectively.
The data in figure 3 illustrated the variation in proline
content in the four plant organs of cv. Giza168.In
roots, proline content remained more or less
unchanged up to 50 mMNaCl, there after it reduced
marginally beyond this level. In stems, proline content
slightly accumulated up to 50 mMNaCl, and then
gives the value of control up to 150 mMNaCl levels.
At the highest salinization levels 300 mMNaCl, it
enhanced greatly. In leaves and spikes, there is no
significant change in proline content, whatever the
salinity levels used.
2 Discussion
From previous results it can be said that cv. Sakha 94
was the most salt tolerant cultivar moreover this
cultivar has halophytic character because stimulation
rather than inhibition was recorded even at the highest
doses of NaCl which could be linked with the success
of breeders to select parents which can produce this
surprising tolerant cultivar followed by cv. Gimiza11
which tolerated NaCl salinity mainly up to the level of
150 mMNaCl salinity but a marked reduction was
observed at the level of 300 mM (about 20%),
surprisingly the production of spike of cv. Giza168
and cv. Gimiza 10 slow down earlier and markedly,
that is while, the production reduced by about 40% at
the level of 20 mM in cv. Gimiza 10, it reduced by
more than 50% at the same salinization level in
wheat cultivar Giza 168 which indicated the great
susceptibility of these cultivars to salinity, these
cultivars cannot be cultivated even at the lowest saline
soil and indicated the unsuccessfulness of the breeding
program of these susceptible cultivars. Accordingly,
the salt tolerance of the four wheat cultivars, during
vegetative growth and crop yield stages ranked as the
following:
cv. Sakha 94> cv. Gimiza 11 >cv. Gimiza 10 > cv.
Giza 168
Interestingly, the differences in the production of spike
among the four wheat cultivars under salinity
conditions were found to be greatly concomitant with
the data of shoot system. cv. Sakha 94 was the
superior in the production of dry matter yield of shoot
system followed by cv. Gimiza 11 and cv. Gimiza 10,
so cv. Giza 168 was the salt susceptible dry matter
producer at the vegetative growth. Thus the
differences in the phenological characters among the
studied cultivars, during vegetative growth draw the
future of crop yield. This was also draw by the
direction of various metabolic processes as well as the
transportation between carbon and nitrogen. It is
worthy to mention that the difference in the salt
