Sugarcane veneer blotch
Pacific Pests, Pathogens and Weeds - Online edition
Pacific Pests, Pathogens & Weeds
Sugarcane veneer blotch (219)
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Common Name
Scientific Name
Deightoniella papuana
Distribution
Only known from Indonesia, Papua New Guinea, Philippines, and Solomon Islands.
Hosts
Sugarcane
Symptoms & Life Cycle
The leaf spots are at first small, oval, light green to pale yellow, with thin red margins. Later, they become surrounded by a number (2-12) of progressively larger spots, each with a light green interior (turning light brown), and outlined by a 0.5-1 mm dark red border (Photo 1). The spots can reach 60 cm long by 1-1.5 cm wide. The spot has a veneer pattern, particularly on the upper surface, hence the name.
The underside of the leaf becomes black as the fungus forms spores.
Spread of the fungus is by airborne spores.
Impact
It is unlikely that this disease causes damage of economic value.
Detection & inspection
Look for the distinct oval spots that become successively surrounded by larger spots as they develop along the leaf blade or midrib.
Management
This is a disease that is not well researched, but it seems unlikely that management is necessary as the damage caused is slight. It is more a curiosity, because of its unique symptoms, than one of economic interest.
AUTHOR Grahame Jackson
Photo 1 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.
