Pacific Pests, Pathogens and Weeds - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Tobacco frog-eye leaf spot (304)

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  • Worldwide distribution. On tobacco, tomato, eggplant, and weeds. Common but minor fungal disease in Oceania.
  • Spots on lower mature leaves at first, moving up plant as season advances. Spots, circular, up to 15 mm diameter, brown, grey or tan, with dark borders, zoned. Centres papery, producing black masses of spores. Spots continue to develop after harvest.
  • Spread as airborne or soilborne spores; possibly, seedborne. Survival in trash  other crops and weeds.
  • Cultural control: remove volunteers; check plants in nursery; avoid overlapping crops; weed; balanced applications of NPK (soil analyses needed); prune infected leaves as soon as spots seen; avoid overhead irrigation; collect, destroy debris after harvest; crop rotation.
  • Chemical control: use chlorothalonil, copper, or mancozeb.
Common Name

Tobacco frog-eye leaf spot

Scientific Name

Cercospora nicotianae

AUTHORS Grahame Jackson & Eric McKenzie
1Information from Graham KM (1971) Plant diseases of Fiji, HMSO, London; and from CABI (2019) Cercospora nicotianae (frog-eye leaf spot of tobacco). Crop Protection Compendium. ( Photo 1 R.J. Reynolds Tobacco Company Slide Set, R.J. Reynolds Tobacco Company, Photo 2 Clemson University - USDA Cooperative Extension Slide Series,

Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.

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