- Widespread distribution. In the tropics. On tomato, papaya (see Fact Sheet no. 300), cucumber (see Fact Sheet no. 189), legumes and probably weeds. An important disease.
- Starts on older leaves, moving upwards rapidly in wet weather, destroying the entire plant.
- Spores are spread in wind-driven rain.
- Cultural control: check all seedling in nursery; do not plant new crops next to old; plant far from papaya (the trees commonly have the same leaf spot disease); remove lower leaves after trusses picked; weed; after harvest, collect trash and burn; tolerant varieties; 3-year crop rotation.
- Chemical control: chlorothalonil, copper, or mancozeb. Start when spots seen, and continue until 3-4 weeks before last harvest.
Pacific Pests, Pathogens, Weeds & Pesticides
Tomato target spot (163)
Photo 1. Target spots, Corynespora cassiicola, on tomato. The larger spots have rings or circles inside them.
Photo 2. Close-up to show the ring patterns in the leaf spots caused by target spot, Corynespora cassiicola, on tomato.
Target spot, leaf spot
AUTHOR Grahame Jackson
Information from Disease management: Target spot of tomato. IPM Florida. IFAS Extension, University of Florida, (https://ipm.ifas.ufl.edu/resources/success_stories/T&PGuide/pdfs/Chapter5/Target_Spot.pdf); CABI (2020) Corynespora cassiicola (target leaf spot of tomato). Invasive Species Compendium. (https://www.cabi.org/isc/datasheet/15467); and MacLenzie KJ et al. (2018) A review of Corynespora cassiicola and its increasing relevance to tomato in Florida. APS Publications. (https://apsjournals.apsnet.org/doi/10.1094/PHP-05-18-0023-RV); and from Corynespora cassiicola (2020) Wikipedia. (https://en.wikipedia.org/wiki/Corynespora_cassiicola).
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.