الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Egypt is famous for its vast desert spaces. About 4/5 the total area
is desert. Only about one-fifth of the total area is cultivated land. In the
western desert of Egypt there are a series of oases which stretching
longitudinally from the north to the far south in a line almost parallel to
the Nile valley. This represents natural depressions rich in natural springs
and wells which are used in agriculture. One of the advantages of this
desert is the presence of wild flora species adapted to a biotic and biotic
stresses. Despite the rarity of wild plant cover in such region, this existing
flora is a treasure of genetic resources. Most of these flora species are
considered as the ancestors of domesticated plants, others have medicinal
benefits either on the popular level or on the documented medicinal
treatments
The Genetic description and phylogeny of some Egyptian Acacia
species and subspecies was investigated in present study by calculating
the morphological variation among Acacia species, detecting biochemical
markers based on peroxidase activity and proline content in Acacia
species, estimate the level of polymorphism among Acacia species using
RABD-PCR markers and determining the genetic relationships between
these species based on the genetic distances.
The present research was carried out at the Faculty of Agriculture,
Saba Basha, Alexandria University and Faculty of Agriculture, Ain
Shames University, Egypt during the seasons of 2011 up to 2013 to study
the morphological, biochemical and molecular genetic markers of some
selected Acacia genotypes as a tool for genetic description for these
genotypes.
Leaves of Acacia genotypes: Acacia tortilis ssp. radiana, Acacia
farnesiana, Acacia stenophylla, Acacia sclerosperma, Acacia saligna
were collected completely randomly from 20 individuals of Acacia tree
natural habitats along different localities in Egypt i.e. Abis station Farm,
Faculty of Agriculture Saba Basha., Borg Al-Arab, Marsa Matroh City
and EL-Gara (Siwa Oasis). Four samples were taken for each parameter.
The following morphological parameters were measured as follow in
vegetative parts of the tree: leaf length (cm), pinna’s length (cm),
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leaflet’s length (mm), spine length (mm) In addition, some qualitative
characters such as the shape of the crown, Growth form: either tree or
shrub as shown, number of stems from ground level
Proline was determined by 3% Aqueous Sulfosalicylic Acid, Acid
Ninhydrin:1.25 gm Ninhydrin ,30 ml glacial acetic acid,20 ml 6M
phosphoric acid .The mixture was warmed with agitation until dissolved
then kept cool at 40C until use.
Five RAPD primers has been developed, in which DNA is
amplified by the polymerase chain reaction (PCR) using arbitrary short
(10 nucleotides) primers .
Concerning to spine length (mm) data indicated clearly high
significant variations among different species. The highest values was
recorded to Acacia tortilis ssp. Radiana collected from (Siwa Oasis),
followed by Acacia tortilis ssp. Radiana (collected from Borg Al-Arab
city) in means 28.75 and 19.25 mm, in respect. The lowest mean value
was recorded to Acacia farnesiana in mean 6.50 mm with LSD =1.36. No
spines were found in the other three species Acacia saligna, A.
sclerosperma and A. stenophylla. Data showed inverse relationship
between the spine and pinna length, epically in the desert localities. The
results showed that Acacia tortilis ssp. Radiana collected from Siwa and
Borg Al-Arab, have the lowest value of pinna length (0.68 and 0.98cm),
respectively, compared with the highest value to (4.28 cm) in Acacia
farnesiana.
For Leaf length (cm) data showed that Acacia sclerosperma and
Acacia saligna have the highest mean values; 23.28 cm and 26.08 cm, in
respect. While the lowest leaf length was recorded to Acacia tortilis ssp.
Radiana collected from (Siwa) (2.85 cm), followed by Acacia tortilis
ssp. Radiana (collected from Borg Al-Arab) by mean (3.15 cm) and
finally Acacia farnesiana in mean 3.80 cm. No significant differences
were observed among species the means ranged from 2.0 to 2.50 mm in
the Acacia tortilis ssp. Radiana collected from (Siwa=2mm), followed by
Acacia tortilis ssp. Radiana (collected from Borg Al-Arab=2.50) and
Acacia farnesiana=2.25mm.
Based on the qualitative data, high similarities were found between
Acacia farnesiana and Acacia tortilis ssp. Radiana in leaves type it were
pinnately compound . On the other hand, Acacia saligna, Acacia