الفهرس 
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Abstract
Most of the developing countries, and in particular arid
and semi-arid regions, are facing serious economic problems.
These problems may be a result of the conflict between the
continuous increase in their populations on one hand and the
limited natural resources and ill-advised land-use methods on
the other hand. A good deal of ecological studies has there-
fore been oriented towards solving these problems, and some
are part~cularly focussed towards the management of salt-affected
ecosystems which occupy about 7.0% of the world surface area
(Massoud 1977). Investigations on the cultivation and utlization
of non-conventional crop plants (such as some of the wild plants
which have an economic potentiality) under salinity and drought
stresses provide evidence that such activities may be ideal
management practices for such types of soils (Zahran 1982).
In Egypt, there are speculations that the introduction of
perennial irrigation in the Nile valley after the construction
of Aswan High Dam has resulted in an increase of salinity and
water logging in some areas. A survey by Raheja (1966) has shown
that more than 300,000 acres have become salt-affected and some
of the most valuable irrigated areas have already gone out of
cultivation. Cumulative halophytes may improve such soils
due to their ability to pump out salts from the soil and ground
water ’through their organs. Boyko (1966) reports that each.