Photo 1. Early symptoms, brown or ghost leaf spot, Cladosporium colocasiae; some spots show a faint darker border.
Photo 3. Underside of the leaf with orange leaf spot, Neojohnstonia colocasiae; spores develop in the spot on the underside of leaves.
Photo 4. Upper surface of leaf with orange leaf spot, Neojohnstonia colocasiae (matching Photo 3); spores develop in the spot on the underside of leaves.
Brown or ghost leaf spot, orange leaf spot, white leaf spot and shot-hole
Cladosporium colocasiae (brown or ghost leaf spot), Neojohnstonia colocasiae (orange leaf spot), Pseudocercospora colocasiae (white leaf spot), Phoma sp.(shot-hole). Phoma sp. is often given as Phyllosticta colocasiicola.
AUTHORS Helen Tsatsia & Grahame Jackson
Photos 2,5&6 (Gerlach WWP (1988) Plant diseases of Western Samoa. Samoan German Crop Protection Project, Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) Gmbh, Germany. Photos 3&4 (taken by Eric McKenzie), and used in this fact sheet, appeared previously in McKenzie E (2013) Neojohnstonia colocasiae. PaDIL - (http://www.padil.gov.au). Photo 6-8 (taken by Eric McKenzie), and used in this fact sheet, appeared previously in McKenzie E (2013) Pseudocercospora colocasiae. 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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