Apple Scab (2016)
    Apple scab is one of the most serious diseases of apple worldwide. In addition to apples, crabapples and mountain ash are also susceptible to apple scab disease. Both the leaves and fruit can be affected. (PLPATH-FRU-23)

Bitter Rot of Apple (2016)
    Bitter rot is a common disease of apples and pears in practically all countries where they are commercially grown. The fungus that causes bitter rot can also cause a leaf spot and canker, although the leaf spot and canker form of the disease are not common in Ohio. (PLPATH-FRU-20)

Fire Blight (2016)
    Fire blight i a common and very destructive bacterial disease of apples and pears. The disease can kill blossoms, fruit, shoots, twigs, branches, and entire trees. (PLPATH-FRU-22)

Apple Powdery Mildew (2008)
    Damage from powdery mildew attack results in stunted growth. The foliage becomes distorted and  twig growth is reduced. Fruit surface may become russetted or discolored, and dwarfed. (HYG-3001-08)

Sooty Blotch and Fly Speck of Apple (2008)
    Sooty blotch and fly speck cause a discoloration or blemish of near-mature fruit. Although all apple varieties are susceptible to infection by both fungi, symptoms are most severe on yellow or light-colored varieties. (HYG-3022-08)

White Rot and Botrysphaeria Canker of Apple (2008)
    The fungus that causes fruit rot can also cause a canker on limbs and other above-ground woody portions of the tree. (HYG-3023-08)

Rusts of Apple (2008)
    Apples are generally most susceptible to infection by the rust fungi during the period from early bloom until about 30 days after bloom. This disease can occur on apple and crabapple in Ohio. (HYG-3024-08)

Black Rot and Frogeye Leaf Spot of Apple (2008)
    Black rot and frogeye leaf spot are phases of a wide-spread and damaging disease of apple and crabapple. (HYG-3030-08)

Necrotic Leaf Blotch of Golden Delicious Apples (2008)
    This is a common but minor disease that appears to be restricted to the Golden Delicious cultivar of apples and its sports. The disease is a physiological disorder and has been observed for about 20 years in most apple-growing areas the Eastern and Midwestern United States. (HYG-3204-08)

Phytophthora Root and Crown Rot of Fruit Trees (2008)
    Phytophthora root and crown rots (sometimes called collar rot) are common and destructive diseases of fruit trees throughout the world. Above-ground symptoms vary between tree species, but generally include reduced tree vigor and growth, yellowing or chlorosis of leaves, and eventual collapse or death of the tree. (HYG-3029-08)


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