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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
Ca > Mg > K, whereas anions have the sequence of: Cl- > SO4= >
HCO3-. Meanwhile, SAR average values (Table.2) was (27.74), in

both seasons, which displays a very high sodium hazard for soil and
plants. High values of SAR for irrigation water cause replacing of

Ca++ and Mg++ ions in the soil, and consequently, damaging of soil
structure and reduction of water availability (Chapman, 1996).

As for the studied heavy metals, they were in the allowable limits
of irrigation water according to FAO (1985). Even though, ground-

water at Wadi Al-Natron can cause some problems due to irrigation
at the along time as a result of heavy metals accumulation.

3.3. Physiological impact of proline on maize plant

3.3.1. Proline accumulation in plant as affected by its original

spray concentrations.

Proline can adapt and adverse stress effect in many plant spe-
cies. Adaptation can be happened through accumulation of proline in

plant leaves (Roberto, et al., 2009). Results of proline accumulation
in maize leaves (Table 3 and Fig. 1) were 0.012, 0.016, 0.014 and

0.013 % for T0, T1, T2 and T3, respectively.

The proline used was directly proportional to accumulation of
proline in plant at T1 treatment, while it was reversely proportional

to proline accumulated in plants at T2 and T3 treatments.

Statistical analysis of proline accumulation showed a significant

effect between T1 and both of T2 and T3. Meanuhile, there was a
significant difference between T0 and each of T1 and T2.

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