Photo 1. Yellow spots on leaves, similar to those from infection by Sweetpotato feathery mottle virus.
Photo 2. Ring spots, possibly from Sweetpotato feathery mottle virus alone, or in combination with other viruses.
Photo 3. Similar to Photo 2, except spots are fading on this older leaf, and there is more "feathering" along the veins.
Photo 4. Purple feathery-like patterns along veins typical of infection from Sweetpotato feathery mottle virus.
Photo 5. Sweetpotato feathery mosaic virus (russet crack strain) causing a narrowing and fissures around the storage root.
Sweetpotato feathery mottle virus, internal cork disease of sweetpotato
Sweetpotato feathery mottle potyvirus; the abbreviation is SPFMV; there are different strains: ordinary (O), russet crack (RC), East African (EA), and severe (S).
AUTHOR Grahame Jackson
Information from CABI (2015) Crop Protection Compendium Sweet potato feathery mottle virus (internal cork disease of sweet potato). (www.cabi.org/cpc); and from Dennien et al. (2013) Growing healthy sweetpotato: best practices for producing planting material. ACIAR Monograph no. 153. Australian Centre pofr International Agricultural Research: Canberra. 176 pp. Photo 2 Sandra Dennien, Gatton Research Facility, DAF, Queensland.
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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