- Worldwide distribution. In the tropics. On a wide range of crops, including, beans and other legumes, capsicum, cucumber and other cucurbits, lettuce, papaya (see Fact Sheet no. 300), tomato. Ornamentals and weeds are also hosts. The fungus causes an important disease of tomato in Pacific islands (see Fact Sheet no. 163).
- Numerous yellow, round or angular spots, bordered by veins, causing leaves to dry out rapidly and fall. Spread by wind-blown rain.
- Cultural control: avoid planting near older infected crops; plant far from blocks of papaya; check seedlings for symptoms; use a trellis to aid air circulation; weed; do not work in the crops when wet; collect and burn trash after harvest; 3-year crop rotation.
- Chemical control: chlorothalonil, copper, mancozeb, start when spots seen, and then at 10-14 day intervals.
Pacific Pests, Pathogens, Weeds & Pesticides
Cucumber target spot (189)
Photo 2. Cucumber target spot, Corynespora cassiicola, causing serious yellowing, wilt and leaf drop on cucumber.
Cucumber target spot, cucumber leaf spot, Corynespora blight
AUTHOR Grahame Jackson
Information from Corynespora blight (Corynespora cassiicola) in Southern Plant Diagnostic Network (undated) Invasive.org. (https://www.invasive.org/collections/viewcollection.cfm?id=3566). Photos 2&3 Konrad Englberger, Pohnpei, Federated States of Micronesia. Photo 4 Kohler F, et al. (1997) Diseases of cultivated crops in Pacific Island countries. South Pacific Commission. Pirie Printers Pty Limited, Canberra, Australia.
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.