Pests Advanced Search Hosts Advanced Search
Alternaria porri (purple blotch of onion )
Alternaria porri
purple blotch of onion
Macrosporium porri, Alternaria allii
Worldwide
Widespread
2021-03-29 18:05:26
fungus
Chile
Allium spp.
ALTEPO
Purple blotch is most severe in hot humid onion climates. Has not been reported in Chile
1 Known Hosts
Allium cepa
onion
Yes
ALTEPO-1,ALTEPO-5,ALTEPO-6
Seed as a pathway uncommon. There are only a few reports of Alternaria porri being detected on onion seeds (ALTEPO-1). Gupta and Pathak, 1988 (ALTEPO-6) were not able to show seed contamination by Alternaria porri
Yes
Agar plating, Blotter plating
Agar plating (ALTEPO-7)
ALTEPO-5,ALTEPO-7
Chemical seed treatments and disinfestation (hot water) are possible, but may be phytotoxic
Newer seed treatment chemicals may be available. Consult with companies suppling seed treatments
ALTEPO-3,ALTEPO-5
ALTEPO-1
Alternaria porri In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc."
ALTEPO-5
Aveling, T. A. S., Snyman, H. G. &Naude, S. P. (1993). EVALUATION OF SEED TREATMENTS FOR REDUCING ALTERNARIA-PORRI AND STEMPHYLIUM-VESICARIUM ON ONION SEED. Plant Disease 77: 1009-1011
ALTEPO-6
Gupta, RB and Pathnak, VM. 1988. Survival of Alternaria porri, inducer of purple blotch of onion. Indian Pathology 41:406-409
ALTEPO-7
Seed Health Testing Method for Alternaria porri On 1.1 National Seed Health System. http://www.seedhealth.org
ALTEPO-3
University of California Pest Management Guides; http://www.ipm.ucdavis.edu/PMG/r584100211.html
Search the database