الفهرس 
Survey of powdery mildew disease in different governoratesOnly 14 pages are availabe for public view
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Abstract
Grapevine (vitis vinefera L.) is one of the most important fruit crops all over the world, especially in tropical regions. It
has many uses as it fresh eaten, non fermented or concentrated
juice and dried into raisins. Fruits of the Egyptian grapes are
very important both for local consumption and exportation. The
cultivated area of grapes in Egypt reached (153956) Fadden
which produced the average of (1531418) tons (Statistics Dept.
Ministry of Agriculture, Egypt 2008).
Grapevine trees are liable to the attack of many pathogens
of which Uncinula necator (Schw.) Burr. causes powdery
mildew disease is very distractive one. This fungus attacks buds,
leaves and fruits causing considerable yield losses. Powdery
mildew symptoms can be seen on foliage, fruit, flower parts and
canes. Mildew usually appears first as whitish or greenish-white
powdery patches on the undersides of basal leaves. It may cause
mottling or distortion of severely infected leaves, as well as leaf
curling and withering. Lateral shoots are very susceptible.
Infected blossoms may fail to set fruits. Berries are most
susceptible to infection during the first three to four weeks after
bloom, but shoots, petioles and other cluster parts are
susceptible all season. Infected berries may develop a netlike
pattern of russet, and may crack open and dry up or never ripen
at all. Old infections appear as reddish brown areas on
dormant canes.