- Worldwide distribution. In tropical, sub-tropical and temperate countries. A wound fungus with many hosts, coffee, cocoa, mango, pineapple, sugarcane, taro. Many strains.
- Spots on the storage roots, and on the stems below ground. Survives as spores in the soil, and as fungus in roots.
- Spread in wind and also by insects – has fruity smell, and spores are sticky. Beetles take spores to wounds.
- Cultural control: if using a nursey to raise cuttings, site nursery on 'new' land; start with 'clean' tip cuttings for planting; avoid wounding storage roots; at harvest, collect trash and burn; avoid (i) packaging and storing crops with signs of the rot, (ii) or storing roots when they are wet; 3-4-year rotations.
- Chemical control: dip storage roots in thiabendizole.
Pacific Pests, Pathogens, Weeds & Pesticides
Sweetpotato black rot (232)
Photo 1. Large, sunken, circular spots on a sweetpotato storage root caused by black rot, Ceratocystis fimbriata.
Photo 2. As in Photo 1, sunken, circular spots on a sweetpotato storage root caused by black rot, Ceratocystis fimbriata. The white cottony growth of the fungus can be seen on some of the spots.
Ceratocystis fimbriata; the asexual state is Chalara species.
AUTHOR Grahame Jackson
Information from Amante V, et al. (2003). A field guide to the sweetpotato problems in the Philippines. The University of Queensland (https://www.soilwealth.com.au/imagesDB/news/Sweet-Potato-Pest-and-Disease-Guide.pdf); and O'Sullivan J et al . Sweetpotato DiagNotes: A diagnostic key and information tool for sweetpotato problems. (http://keys.lucidcentral.org/keys/sweetpotato/key/Sweetpotato%20Diagnotes/Media/Html/FrontPage/FrontPage.htm); and from Nelson SC (undated) Black rot of sweet potato: disease cycle and management. CTAHR, Hawaii. (https://www.ctahr.hawaii.edu/nelsons/BlackRotofSweet%20Potato.pdf). Photo 1 Gerald Holmes, California Polytechnic State University at San Luis Obispo, Bugwood.org. Photo 2 Charles Averre, North Carolina State University. Bugwood.org. Photo 3 Compendium of SweetPotato Diseases (1988). American Phytopathological Society.
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.