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Mohamed Rashwan
The saline habitats are more prevalent in dry areas of these
countries. Salinization, or development of salt affected soils, is one

of the internal pedogenic processes that lead to soil degradation and
thus land desertification. The salt accumulation may contribute to a
partial or complete loss of the soil capacity to provide the required

amounts of water to plants, changing fertile lands to «deserts». Fre-
quently, salinization process practically creates irreversible chemical

or physical internal soil degradation.

Salinity problems appear as a consequence of’ salt accumulation
in soil-root zones and depths, where soil moisture regime is charac-
terized by strong losses of water by evaporation and transpiration,

and by reduced leaching of the remaining salts.

Exploring suitable ameliorants or stress alleviant is one of the
tasks of plant biologists. In recent decades, exogenous protectant

such as osmoprotectants (proline, glycinebetaine, trehalose, etc.),
plant hormone (gibberellic acids, jasmonic acids, brassinosterioids,
salicylic acid, etc.), antioxidants (ascorbic acid, glutathione, tocoph-

erol, etc.), signaling molecules (nitric oxide, hydrogen peroxide,
etc.), polyamines (spermidine, spermine, putrescine), trace elements
(selenium, silicon, etc.) have been found effective in mitigating the

salt induced damage in plant (Yusuf et al., 2012).

These protectants showed the capacity to enhance the plant’s
growth, yield as well as stress tolerance under salinity. Some amino

acids such as proline have been used to reduce salt stress damage to
salt-sensitive plants, the foliar application of proline increased plant
height, number of branches, fresh and dry weights of aerial vegeta-

tive parts (Gamal El-Din and Abd El-Wahed, 2005).

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