Photo 1. Small, dark angular spots of Alternaria leaf spot caused by Alternaria dauci. During humid weather the spots join together developing into a blight - a rapid death of the leaves.
Carrot leaf spot, Alternaria leaf spot of carrot
Alternaria dauci. Note, another fungus, Cercospora carotae, produces similar symptoms.
AUTHOR Grahame Jackson
Information (and Photo 1) is from Diseases of vegetable crops in Australia (2010). Editors, Denis Persley, Tony Cooke, Susan House. CSIRO Publishing; and from Gerlach WWP (1988) Plant diseases of Western Samoa. Samoan German Crop Protection Project, Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) Gmbh, Germany. Photo 2 Kohler F, Pellegrin F, Jackson G, McKenzie E (1997) Diseases of cultivated crops in Pacific Island countries. South Pacific Commission. Pirie Printers Pty Limited, Canberra, Australia. Photo 3 David B. Langston University of Georgia. Photo 4 McKenzie E (2013) Alternaria dauci PaDIL - (http://www.padil.gov.au).
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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