الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Cereal grains have been the principal component of
human diet for thousands of years and have played a major
role in shaping human civilization. Around the world, rice,
wheat, and maize, and to a lesser extent, sorghum and millets
are important staples critical to daily survival of billions of
people. More than 50%, reaches values exceeding 80% in the
poorest countries, of world daily caloric intake is derived
directly from cereal grain consumption (Awika, 2011).
Cereals constitute about 55% of the African food basket
and for every 1% increase in food prices, food expenditure in
developing countries decreases by 0.75% (FAO, 2006).
Egypt is amongst the highest importers of cereals in the
world as it has occupied the fourth rank (16.8 million tons) of
the top ten grain importers in the world (EPI, 2013) and is
the largest wheat importer (Abdel-Razek, 2013; European
Bank for Reconstruction and Development, 2013 and
FAO, 2014).
In the developing countries, the problem of competition
from insect pests is further complicated with a rapid annual
increase in the human population (2.5-3.0 percentage) in
comparison to a 1.0 percentage increase in food production.
In seeking to make improvements to cereal grain supply,
an important element to consider is postharvest losses
(PHLs), major donors have recently been focusing on loss reduction strategies (FAO/AfDB, 2009 and World Bank,
2010).
Insect infestations have been reported as the major cause
of food grain losses in most developing countries (Talukder
et al., 2004). Protection of various agricultural crops against
insect pests that cause severe economic damage is an issue
being researched worldwide (Hilder and Boulter., 1999;
Kramer et al., 2000; Flinn et al., 2006). One of many
possibilities to achieve higher productivity in agricultural
crops is to use pesticides for crop protection. But, pesticide
residues can contaminate the environment, food and many of
them are poisonous to humans and other organisms
(Snedeker, 2001).
Transgenic biotechnology can be utilized as an alternative
choice for preservation of crops during storage from attack
by insect pests using insect growth-inhibiting proteins, e.g.,
proteinase inhibitors (Ohtsubo and Richarson, 1992; Yoza
et al., 2002 and Oppert et al., 2003).
There are many biocidal proteins that occur in nature,
which are potential biopesticides for stored-grain protection.
One strategy involves using transgenes to control a wide
range of pests. The insecticidal activity of chicken avidin
protein has been known since the year 1959 when it was first
reported as a toxin to the housefly, Muscadomestica (L.),
when administered in the diet to larvae (Levinson and
Bergmann, 1959). Avidin protein causes mortality in many species of stored-product insects by preventing the
absorption of dietary biotin (Morgan et al., 1993). This gene
has been incorporated into many plants and these transgenic
plants showed remarkable resistant to stored products insects
(Kramer et al., 2000; Burgess et al.,2002; Markwick et
al.,2003; Yoza et al., 2005 and Cooper et al., 2009).
The objective of this thesis was to develop transgenicwheat
plants expressing the modified avidin gene, coding for
a protein lethal to stored cereals insects, so can act as a
biopesticide alternative to traditional chemical insecticides
through the following steps:
1. Construction of the plant expression plasmid vector
carrying a modifiedavidin gene as well as the selectable
marker bar gene.
2. Genetic transformation of the Egyptian bread wheat
cultivar (Giza 168) with this construct using biolistic gene
gun.
3. Molecular analyses of the transgenic plants, to assess the
presence and integration of the avidin gene and ensure its
expression.
4. Challenging the avidin transgenic wheat flour with the
grain weevil (Sitophilus granarius) to test their insecticidal
effect.