Increase in foliar osmotic potential to soil osmolality has been previously realized
by the senior author and some other investigators. The present study has been carried
out to clarify the interactive kinetin and salinity stress on osmotic potential and carbohydrate
contents in cotton and millet plants. Kinetin solution (10 ppm) was applied in
three different modes; presoaking of seeds, spraying of shoot system and with irrigation
water. This study revealed that kinetin increased the osmotic pressure in the two
experimental plants when applied by spraying and irrigation with water. However the
osmotic pressure was reduced when the seeds were presoaked in kinetin solution. It was
concluded that kinetin can alleviate the effect of salinity stress on the osmotic pressure.
The carbohydrate contents of various treated plants were also taken into consideration.

Wadi Quena, unique in its north-south orientation
among other wadies of the eastern desert of Egypt
constitutes a vast catchment system of sporadic rains
over the Red Sea mountains. The present study concerns
a part of this catchment area, including some eastwest
tributaries pouring flood waters into the lower
part of the main trunk of the wadi. Due to local
physiographic factors, these tributaries harbour two
communities newly recognized in this desert. These are:
community of Salsola haryosma-Tamarix aphylla and
community of Cilrullus colocynlhis-Cleome droserifolia.
Elements of the alliance Zygophyllaeion coccini, previously
identified in this series of investigations, are well
represented in the area under consideration.

Wadi Quena, unique in its north-south orientation
among other wadies of the eastern desert of Egypt
constitutes a vast catchment system of sporadic rains
over the Red Sea mountains. The present study concerns
a part of this catchment area, including some eastwest
tributaries pouring flood waters into the lower
part of the main trunk of the wadi. Due to local
physiographic factors, these tributaries harbour two
communities newly recognized in this desert. These are:
community of Salsola haryosma-Tamarix aphylla and
community of Cilrullus colocynlhis-Cleome droserifolia.
Elements of the alliance Zygophyllaeion coccini, previously
identified in this series of investigations, are well
represented in the area under consideration.

Wadi Quena, unique in its north-south orientation
among other wadies of the eastern desert of Egypt
constitutes a vast catchment system of sporadic rains
over the Red Sea mountains. The present study concerns
a part of this catchment area, including some eastwest
tributaries pouring flood waters into the lower
part of the main trunk of the wadi. Due to local
physiographic factors, these tributaries harbour two
communities newly recognized in this desert. These are:
community of Salsola haryosma-Tamarix aphylla and
community of Cilrullus colocynlhis-Cleome droserifolia.
Elements of the alliance Zygophyllaeion coccini, previously
identified in this series of investigations, are well
represented in the area under consideration.

The effect of treatment combinations of decreased soil osmotic water potential (Ips) and increased
sodicity (SAR) on chlorophyll (ChI) characteristics (ChI a and b contents, Chi a/b ratio, and Chi
stability to heat - CSI) of three crop plants (Gossypium barbadense L., Hibiscus sabdarifJa L. and
Sorghum bicolor L.) was studied. Chi characteristics in different plant species responded variably
to both changes in 1jJs and sodicity. Generally, Chi content was not sensitive to sodicity but both
ChI a and b were significantly affected by osmotic stress. Accordingly, the Chi a/b apparent changes
at different SAR levels were due to osmotic rather than sodic effects. CSI showed variable trends in
response to both decreased 1jJs and increased sodicity according to ChI type and plant species.
Decreasing ChI content and increasing CSI, under reduced 1jJs, might indicate the adaptations
of plants toward enduring salinity stress, particularly in reference to the ecological origin of such
crop plants.

The effect of treatment combinations of decreased soil osmotic water potential (Ips) and increased
sodicity (SAR) on chlorophyll (ChI) characteristics (ChI a and b contents, Chi a/b ratio, and Chi
stability to heat - CSI) of three crop plants (Gossypium barbadense L., Hibiscus sabdarifJa L. and
Sorghum bicolor L.) was studied. Chi characteristics in different plant species responded variably
to both changes in 1jJs and sodicity. Generally, Chi content was not sensitive to sodicity but both
ChI a and b were significantly affected by osmotic stress. Accordingly, the Chi a/b apparent changes
at different SAR levels were due to osmotic rather than sodic effects. CSI showed variable trends in
response to both decreased 1jJs and increased sodicity according to ChI type and plant species.
Decreasing ChI content and increasing CSI, under reduced 1jJs, might indicate the adaptations
of plants toward enduring salinity stress, particularly in reference to the ecological origin of such
crop plants.

Sand culture technique was employed to investigate the effect of soil salinity and kinetin on chlorophyll a and b contents, the a/b ratio and the chlorophyll stability to heat in Sorghum bicolor and Gossypium barbadense cultivars. Levels of osmotic potential of the soil solution between -3 and -13 bar were adjusted by irrigation
with certain amounts of saline solutions containing NaCI and CaCI2. Kinetin solutions
(10 ppm) were applied by 3 methods: treatment of the seeds (presoaking), shoot
treatment (spraying) and by irrigation. Kinetin can retain the chlorophyll content and
even increases them in the two investigated plants when applied by presoaking method. The a : b ratio seems to be affected by salinity stress rather than by kinetin treatment. Kinetin enhances significantly the stability index of both chlorophyll types in particular when applied by presoaking method. The results proved that kinetin can alleviate salinity stress on chlorophyll parameters in both investigated
plants when applied by presoaking method rather than by the other methods

Five wadis proliferate in the area surveyed (latitudes
27°-28 N and longitudes 33°-34 E) drain this part of
the Red Sea mountains into the sea (lower Gulf of
Suez)./This wadi system have distinguished variation
in geomorphological and edaphic characteristicS. ACcordingly four associations phytosociologically identified are reflections of such variations. Such associations are not repetitions to those identified before in this series of investigations. Also, they have no analogues among communities recognized in this desert by other investigators.

Five wadis proliferate in the area surveyed (latitudes
27°-28 N and longitudes 33°-34 E) drain this part of
the Red Sea mountains into the sea (lower Gulf of
Suez)./This wadi system have distinguished variation
in geomorphological and edaphic characteristicS. ACcordingly four associations phytosociologically identified are reflections of such variations. Such associations are not repetitions to those identified before in this series of investigations. Also, they have no analogues among communities recognized in this desert by other investigators.

Five wadis proliferate in the area surveyed (latitudes
27°-28 N and longitudes 33°-34 E) drain this part of
the Red Sea mountains into the sea (lower Gulf of
Suez)./This wadi system have distinguished variation
in geomorphological and edaphic characteristicS. ACcordingly four associations phytosociologically identified are reflections of such variations. Such associations are not repetitions to those identified before in this series of investigations. Also, they have no analogues among communities recognized in this desert by other investigators.