الفهرس 
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Abstract
Plant genetic resources are being eroded through destruction and
degradation of natural habitats, intensification of cultivation of arable lands,
expansion of cultivation into marginal areas, replacement of land races by new
cultivars, woodcutting, and overgrazing of natural pastures and range lands. In
general, habitat degradation and fragmentation may restrict gene flow and result
in genetic differentiation among populations that previously did not exist. In turn,
this may affect the life history traits and the probability of species extinction
(Bawa et. aI., 1991 and Geburek, 1997). Such massive destruction of genetic
resources is particularly evident in the Middle East, and the need for conservation
of these resources is urgent. This region is the center of origin of many crops and
fodder plants and one of the richest centers oflegumes (more than 2,000 species)
in the Northern Hemisphere. In the local floras there are many plant species
which can be considered as wild ancestors or close relatives of cultivated
legumes, and a source of desirable genes for cultivated varieties and the supply of
new crops as species of: Trigonella, Vicia, Lathyrus, Trifolium, Onobrychis,
Medicago, Melilotus, Lotus and Orthnithopus. Besides, the populations of these
species include genetic traits of adaptation to environmental stresses, like drought
and salinity resistance, that can be valuable in genetic engineering of cultivated
varieties (Barkoudah, 1996).
The genus Trigonella includes species of considerable economic value.
T. fcenum-groecum has been considered as one of the most important medicinal
plants since very ancient times. Apart from sugar, protein and other ingredients.