Scab: apple

Other materials based on EDA have also been suggested as fungicides. The most important of the imida2oline type (162) is 2-heptadecyl-2-imida2oline (163), prepared from EDA and stearic acid [57-11-4]. It is used as the acetate salt for control of apple scab and cherry leaf spot. A 2 1 EDA—copper sulfate complex has been suggested for control of aquatic fungi (164). 

Apfelsilure, Apfelsaure, /. malic acid. Apfel-schorf, m. apple scab. sine, /. (aweet) orange. 

Apples Scab Venturia inaequalis Bordeaux mixture... 

Larbi M, Gobat JM, Fuchs JG (2006) Inhibition of the apple scab pathogen venturia inaequalis and the grapewine downy mildew pathogen plasmopara viticola by extracts of green waste compost. ORBIT Conference... 

Fungal diseases are grouped according to the type of disease (or symptoms) that they cause, such as mildews, molds, or rots. Most spread from plant to plant in the form of spores. Some, like clubroot, have dormant spores that can remain viable in the soil for 40 years or more. The fungus that causes apple scab overwinters on infected debris such as leaves on the ground. Fungal diseases are more common in warm, damp conditions, which allow the spores to move freely in moist air and on a film of water on the surface of leaves. 

This fungal disease overwinters in leaf debris, and in severe cases in twig lesions, and is spread to new leaves in spring by wind and rain. Apple scab is worse when the weather is cool, wet or overcast in spring and early summer, especially at flowering time. 

Fungal disease similar to apple scab (q.v.) but infection also often occurs on bud scales. Scab is worse in cool, wet periods in spring and early summer. 

Bean PM Cuke A Rice Blast Apple Scab Bean Rust (Systemic) ... 

Sulfur sprays More severe apple scab Venturia inaequalis), similar orange tortrix Argyrotaenia citrana) Vossen et ai. (1994)... 

Sulfur-Based Pesticides. Sulfur (elemental) has been used as an effective acaricide, fungicide, and insecticide. For ease of use, a number of special formulations are available, ranging from sulfur dusts (up to 95% sulfur) a wettable powder (30 to 90%) and paste-like solutions in which the sulfur is ground to a fine colloidal form. Such formulations may contain up to 50% sulfur. Target plant diseases of sulfur when used as a fungicide include apple scab, brown rot. downy and powdery mildew, and peach scab. Against insects, sulfur is effective for mite, scale, and tJirip. Most formulations are not injurious to honeybees. 

In apple, the glycoside phloridzin (1.27) and its aglycone phloretin are thought to inhibit the apple scab fungus Venturia inaequalis. Phloridzin is also an ort/20-dihydroxyphenolic compound, and, like chlorogenic acid, can also be easily converted to a reactive quinone upon attack by a pathogen. Raa (1968) demonstrated that oxidation products of phloridzin inhibit fungal... 

Nicholson, R. L., and Rahe, J. E., 2004, Apple scab and its management, in Fruit and vegetable diseases Mukeiji., K. G., ed., Kluwer Academic Publishers, Dordrecht, pp. 41-58. 

Influence of Bitertanol on the Pathogenesis of Venturia inaequalis (Apple Scab). Apple scab is the most serious disease of apples and... 

The disease cycle of apple scab (Venturia lnaequalis) starts in spring with ascospores, which are discharged from asci, causing primary infection in the new leaves. During the summer, several generations of asexually formed conidia are produced which may cause infection in the same way as ascospores do. 

Spore germination of Venturia inaequalls, the apple scab fungus, is also unaffected by the studied azole fungicides. They prevent... 

Figure 13. Suppressed development of the apple scab fungus in a leaf that was treated with bitertanol before inoculation (photographed 3 days post-inoculation). (Reproduced with permission from Ref. 1. Copyright 1981 Pflanzenschutz-Nachrichten Bayer.)...

Brandes, W., and Paul, P. (1981) Studies on the Effect of Baycor on Apple Scab Pathogenesis, Pflanzenschutz-Nachrichten Bayer 34, 48 - 59. 

Paul, V. (1981) Biology of Venturia inaequalis (Cooke) Winter, the Pathogen of Apple Scab, Pflanzenschutz-Nachrichten Bayer 34, 60 - 74. 

Paul, V., and Brandes, W. (1983) Scanning Electron Microscopy Studies on the Pathogensis of Apple Scab and its Control with Baycor, Pflanzenschutz-Nachrichten Bayer 36, 21 - 37. 

Figure 2. Densely sporulating lesions of apple scab on an unsprayed leaf (left) compared with chlorotic nonsporulating lesions on a leaf sprayed with etaconazole (right).

Ellis, M.A., Madden, L.V., and Wilson, L.L. 1984. Evaluation of an electronic apple scab predictor for scheduling fungicides with curative activity. Plant Dis. 68 1055-1057. 

A microcomputer-based instrument to predict primary apple scab infection periods. Plant Dis. 64 69-72. 

Kelley, R.D., and Jones, A.L. 1981. Evaluation of two triazole fungicides for post-infection control of apple scab. Phytopathology 71 737-742. 

Schwabe, W.F.S., and Jones, A.L. 1983. Apple scab control with bitertanol as influenced by adjuvant addition. Plant Dis. 67 1371-1373. 

Schwabe, W.F.S., Jones, A.L., and Jonker, J.P. 1984. Greenhouse evaluation of the curative and protective action of sterol-inhibiting fungicides against apple scab. Phytopathology 74 249-252. 

Apple scab (Venturis inaequalis) fungicidal activity, 135 influence of bitertanol on pathogenesis, 79... 

Penthiopyrad [218,219] is a new carboxamide fungicide under development by Mitsui Chemicals that shows good activity against Botrytis, powdery mildew, and apple scab. 

Folpet is a protective leaf fungicide. Its mode of action inhibits normal cell division of a broad spectrum of microorganisms. It is used to control cherry leaf spot, rose mildew, rose black spot, and apple scab. It is used on berries, flowers, ornamentals, fruits and vegetables, and for seed- and plant-bed treatment. Folpet also finds use in paints, plastics, and treatment of internal and external structural surfaces of buildings to control fungal attack.50,52... 

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