Apple scab fungicidal activity

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. 

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. 

Tolkmith (1966) developed the active substance 0,0-diethyl phthalimidophos-phonothioate (ditalimfos 36), which is a very effective fungicide against powdery mildew in apple and cherry orchards, cucumbers and roses, and is also effective against apple scab ( Venturia inaequalis) and diseases caused by Monilia fructicola, etc. (Huisman, 1972 Huisman and Peskett, 1973). In addition to its protective effect ditalimfos also has a curative action, and is virtually nontoxic to warm-blooded organisms. 

Many compounds containing the N—S—CCI3 grouping have been shown to have broad-spectrum potent fungicidal activity. Captan is the best-known example and was introduced in the early 1950s as a seed dressing and for the control of apple and pear scab and botrytis. Note its easy and cheap synthesis which commences with a Diels-Alder reaction. 

Benzimidazoles. The best-known examples, which were introduced in 1967/8, are Benomyl and Thiabendazole. Both have been widely accepted as broad-spectrum systemic fungicides active against botrytis, powdery mildews, apple scab and as a seed dressing against common bunt of wheat. 

Because of their after-infection and antisporulation activity against scab, the EBI fungicides are especially suitable for use in predictive disease control programs. Predictive disease control is an important part of integrated pest management programs on apples. A predictive system means control measures are applied after the onset of infection. Small special purpose computers with field... 

For tree fruits such as apples (Table IX), low rates of 2-4 grams active ingredient per 100 liters of spray give near-perfect control of both major diseases, scab and powdery mildew excellent cedar apple rust control is also observed at these rates. Standards for these tests include both sterol inhibitors (fenarimol and bitertanol) and non-systemic protectant fungicides (sulfur and captan). 

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