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EFFECT OF SOME AMINO ACIDS ON THE PHYSIOLOGICAL CHARACTERISTICS OF
MAIZE PLANT UNDER SOIL SALT STRESS CONDITIONS IN EGYPT AND TUNISIA
Problems of salinization and water logged soils in Tunisia al-
ready largely affect on part of irrigated areas of the Mejerda Valley

and the Center of Tunisia and the oasis in the south. mainly in the
central and southern parts of the country. Salt-affected soils occur to
a considerable extent in irrigated areas. The aridity conditions and

high potential evapotranspiration, saline groundwater and seawater
intrusion, poor water management/agronomic practices, use of low

quality water for irrigation without proper management are the major
causes of salt-affected soils commonly formed in depressions and
low lying parts of the landscape. On the geochemical aspect, sodium

chloride paths dominate all the saline soils in these areas of Tunisia,
as well as, less soluble salt as calcium carbonate and gypsum. The
major alkaline cations in these soils are calcium, magnesium, sodium

and potassium combined with the anions of chlorides, sulfates or car-
bonates, which differ in their solubility. In a homogeneous climatic
region and for the same soil moisture regime, more salt is soluble,

more easily and quickly it will be leached outside the profile and
outside the basin (Hachich et al., 1994).

The objectives of the study were:

1 - To evaluate the effect of proline foliar application on the accumu-
lation of ions in saline sensitive plants due to salinity stress that
may have been caused by the high concentration of salts in soil
irrigated with saline water;

2 - The possible beneficial effects result from the use of proline foliar
application at different concentration were (15, 30 and 45 ppm)
during the growing stages of salt-sensitive plants (Maize class
Hybrid singles White 128) in order to reach the best possible
productivity.

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