Allium cepa
onion
31 Related Pests
Alternaria porri
fungus
Macrosporium porri, Alternaria allii
Worldwide
Widespread
Chile
2021-03-29 18:05:26
Purple blotch is most severe in hot humid onion climates. Has not been reported in Chile
Allium spp.
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
Agar plating (ALTEPO-7)
ALTEPO-1,ALTEPO-5,ALTEPO-6,
Agar plating, Blotter plating
ALTEPO-5,ALTEPO-7,
Agar Plating is s standard method of the NSHS
Chemical seed treatments and disinfestation (hot water) are possible, but may be phytotoxic
ALTEPO-3,ALTEPO-5,
Newer seed treatment chemicals may be available. Consult with companies suppling seed treatments
Alternaria porri In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc."
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
Gupta, RB and Pathnak, VM. 1988. Survival of Alternaria porri, inducer of purple blotch of onion. Indian Pathology 41:406-409
Seed Health Testing Method for Alternaria porri On 1.1 National Seed Health System. http://www.seedhealth.org
University of California Pest Management Guides; http://www.ipm.ucdavis.edu/PMG/r584100211.html
Tobacco streak virus
virus
Annulus orae, Asparagus stunt virus, Black raspberry latent ilarvirus, Datura quercina virus, New logan virus, Micotiana virus 8, Nicotiana virus vulaerans, Tobacoo streak ilarvirus, Tracttus orea
Worldwide
CA, CO, FL ID IA, KT, MA, MI, MN, NC, OH, OK, OR, PA, WA, WI
Korea, Thailand
2022-11-04 18:19:53
Requires thrips to transmit from plant to plant.
Extensive host range includes many weeds, fruit and ornamental plant species. Over 70 species reported as hosts. The vegetables and agronomic crops listed below are important hosts of Tobacco streak virus
No
TSV000-1,
Seed as a pathway is not known to occur.
TSV000-1,
Tobacco Streak Virus. In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Tomato black ring virus
virus
Lettuce Ringspot Virus, Bean Ringspot Virus, Beet Ringspot Virus, Celery Yellow Vein Virus, Lettuce Ringspot Virus,Potato Bouquet Virus, Potato Pseudo-Aucuba Virus,Tomato Black Ring Nepovirus
India, Japan, Turkey, throughout Europe
Not known to occur
China, Korea, Mexico, Thailand
2022-11-03 18:40:04
Wide host range reported. Requires the Dagger nematode to transmit this virus
Wide host range, however many are experimental only. Important crops listed below.
No
RICH ISTA,ISF RPLD,TBRV00-2,TBRV00-3,
Pathway not proven. No references found indicating seed is a pathway. Older literature (TBRV00-2, TBRV00-3) lists seed as a possible pathway, but no evidence of seed transmission was presented for this host. Seed pathway inferred due to other hosts or nepoviruses possible seed pathway.
RICH ISTA,ISF RPLD,TBRV00-2,TBRV00-3,
Richardson, MJ. 1990. An Annotated List of Seedborne Diseases. International Seed Testing Association, Zurich Switzerland.
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Lister RM, Murant AF, 1967. Seed-transmission of nematode-borne viruses. Annals of Applied Biology, 59:49-62.
Murant AF, Lister RM, 1967. Seed-transmission in the ecology of nematode-borne viruses. Annals of Applied Biology, 59:63-76.
Ditylenchus dipsaci
nematode
Anguillula devastatrix, Anguillula dipsaci, Anguillula secalis, Anguillulina dipsaci,Anguillulina dipsaci var. communis, Ditylenchus allocotus, Ditylenchus amsinckiae, Ditylenchus dipsaci var. tobaensis, Ditylenchus fragariae,Ditylenchus sonchophila, Ditylenchus trifolii, Tylenchus allii Tylenchus devastator, Tylenchus devastatrix
Tylenchus dipsaci, Tylenchus havensteini, Tylenchus hyacinthi, Tylenchus putrefaciens
Worldwide in temperate climates.
Widespread
Brazil
2023-05-05 19:09:29
Ditylenchus dipsaci is known to attack over 450 different plant species, including many weeds. There are approximately 20 biological races known that tend to prefer certain hosts.
Yes
DITYDI-3,DITYDI-5,ISF RPLD,
Seed is known to be a pathway.
DITYDI-3,DITYDI-5,ISF RPLD,
Sieve Method
CABI CPC,
Used for research. This method has not been standardized or validated.
Seed fumigation
DITYDI-3,ISF RPLD,
Crop rotation with non-hosts and fumigation most effective. Quality seed production practices with inspection.
Green and Sime, 1979. The Dispersal of Ditylenchus dipsacii in vegetable crops. Annals of Applied Biology 92; 263-270
Seinhorst JW, Koert JL, 1971. Stem nematodes in onion seed. Gewasbescherming 2:25-31.
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Burkholderia gladioli pv. allicola
bacterium
Phytomonas allicola, Pseudomonas allicola, Pseudomonas gladioli pv allicola
Israel, Australia, New Zealand, Brazil
Not known to occur
China, Korea
2021-10-26 21:22:13
Primarily isolated from soil or wet onion residues.
The only natural host is onion. Artifical inoculation includes iris, tulip, narcissus and carrot
No
PSDMGA-2,PSDMGA-3
No references found indicating seed as a pathway for this pathogen.
PSDMGA-2,PSDMGA-3
Candidatus phytoplasma asteris
phytoplasma
Worldwide
Widespread
2021-11-15 19:27:42
AY phytoplasmas are not seed transmissable and seed is not a pathway in any host.
Wide host range, primarily herbaceous dicots, though strains infect monocots and woody ornamentals
No
PHY01-1,PHY01-2,
Seed is not a pathway for AY phytoplasmas
PHY01-1,PHY01-2,
Aphelenchoides fragariae
nematode
Aphelenchoides olesistus, Aphelenchoides olesistus var. longicollis, Aphelenchoides pseudolesistus
Worldwide, though limited reports in Africa, South America, Canada, Caribbean
Widespread
China
2023-08-21 22:00:59
This nematode has been reported in China
Primarily a pest of strawberry, ferns, ornamentals and flowers of the Liliaceae family. Reported in onion, but not confirmed as a host.
No
APLOFR-1,APLOFR-3,ISF RPLD,NEMAPLEX,
Not a host. Onion is not known to be a natural host though listed in APLOFR-1 as an uncommon and unimportant host. No references were found to verify that onion is a host.. Only literature found indicates seed of Anthrium may be a pathway for this nematode (APLOFR-1).
APLOFR-1,APLOFR-3,ISF RPLD,NEMAPLEX,
Hunter, Ko, Kunimoto, and Higaki. 1974. A Foliar Disease of Anthurium Seedlings Caused by Aphelenchoides fragariae. Phytopathology 64; 267-268.
Aphelencoides fragariae In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Ferris, H. 2019. Nemaplex. www.nemaplex.ucdavis.edu.
Verticillium albo-atrum
fungus
Verticillium albo-atrum var. caespitosum, Verticillium albo-atrum var. tuberosum
Worldwide, primarily in cool temperate climates and in potato producing areas
Widespread, especially in northern states
China, Thailand
2022-11-11 17:40:00
Many reports of Verticillium albo-atrum in crops reported prior to 1970 may have actually been Verticillium dahlia. Only lucerne, potatoes, tomatoes and hops are considered important hosts. This pathogen has been reported in China
Wide host range. An important pathogen of potatoes.
No
VERTAA-2,VERTAA-9,ISF RPLD,
Several references indicate that onion may be attacked by this fungus, but most references cannot be confirmed or no data was presented. Nonetheless, there is no evidence indicating that seed is a pathway.
VERTAA-2,VERTAA-9,ISF RPLD,
Anonymous 1960. Index of Plant Diseases in the United States. U.S.D.A. Agric. Handb. 165: 1-531. (94)
Richardson, MJ. 1990. Annotated List of Seedborne Diseases, Fourth Ed. International Seed Testing Association. Zurich, Switzerland
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Urocystis cepulae
fungus
Tuburcinia cepulae,
Urocystis colchici var. cepulae,
Urocystis magica, Tuburcinia magica,
Urocystis allii,
Tuburcinia allii,
Tuburcinia oblonga,
Urocystis oblonga
Worldwide
Widespread, though considered restricted to the areas reporting the disease
China
2022-09-22 18:42:52
This pathogen has not been reported in China
onion, leek, garlic
No
UROCCE-3,UROCCE-4,
Seed is not known to carry this fungus in trade. Urocystis cepulae teliospores have occasionally been found unattached to seed in seed lots, but seed transmission has not been proven. Seed conditioning should remove any associated fungal spores and physical purity testing should verify removal of any potential contaminate.
Physical purity testing by standard AOSA or ISTA methods
UROCCE-3,UROCCE-4,
Physical purity
AOSA/SCST,ISTA,
Physical purity to verify that fungal spores are not associated loosely with seed lots
UROCCE-1,
Most seed treatments applied to seed lots are to protect emerging seedlings from soil borne infections.
Mulder JL, Holliday P, 1971. Urocystis cepulae. Commonwealth Mycological Institute Descriptions of pathogenic fungi and Bacteria No. 298. Wallingford, UK: CAB International.
International Seed Federation Regulated Pest List Database. www.pestlist.worldseed.org., Nyon, Switzerland
AOSA Rules for Seed Testing; www.analyzeseeds.com
International Rules for Seed Testing. International Seed Testing Association; www.seedtest.org
Urocystis cepulae In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Tomato ringspot virus
virus
Tomato ringspot nepovirus, Blackberry (Himalaya) mosaic virus, Euonymus chlorotic ringspot virus, Euonymus ringspot virus, Grape yellow vein virus, Grapevine yellow vein virus, Nicotiana 13 virus, Peach stem pitting virus, Prune brown line virus, Prunus stem pitting virus, Red currant mosaic virus, Tobacco ringspot virus 2, Winter peach mosaic virus
Worldwide
Widespread, primarily along the Pacific coast, NY, PA
Korea, Mexico, Thailand
2022-11-07 17:26:14
Natural spread is confined to areas where there are moderate to high populations of nematode vectors belonging to the genus Xiphinema. Requires the nematode to spread. Seed transmission only shown in strawberry and raspberry in nature.
Wide host range, primarily ornamentals and fruit trees. Vegetable crops infected are listed below. Not known to infect grains and grasses
No
TORSV0-2,TORSV0-4,TORSV0-5,
No references found indicting onion is infected by this virus
TORSV0-2,TORSV0-4,TORSV0-5,
Brunt, AA, Crabtree, K., Dallwitz, MJ, Gibbs, AJ, Watson, L. and Zurcher, EJ. (eds.). Plant Viruses Online: Descriptions and Lists from the VIDE Database, Version: 16th 1997. http://bio-mirror.im.ac.cn/mirrors/pvo/vide/refs.htm
International Seed Federation Pest List Database. http://www.worldseed.org Nyon Switzerland
Richardson, MJ, 1990. An Annotated List of Seed-borne Diseases. International Seed Testing Association, Zurich Switzerland
Tobacco mosaic virus
virus
TMV U1, type, Vulgare or Common strain
tobacco mosaic tobamovirus,
VMT (Virus mosaique de tabac)
Worldwide
Widespread
Mexico
2023-08-21 16:58:52
Broad host range. Cultivated species listed below.
No
TMV000-1,TMV000-11
No references found indicating that A. cepa is a host for TMV.
TMV000-1,TMV000-11
Tomato spotted wilt virus
virus
Tomato spotted wilt tospovirus, Tomato spotted wilt virus group
Worldwide
Widespread
2023-08-21 17:00:09
Seed is not a pathway for Tospoviruses, including Tomato spotted wilt virus
Wide host range. Over 800 plant species are known hosts. Primarily ornamentals,flowers. No evidence that small grains or corn are hosts.
No
TSWV00-1,TSWV00-2,
Seed is not a pathway for Tospoviruses, including Tomato spotted wilt virus. No evidence that onion is a host.
TSWV00-1,TSWV00-2,
Botryotinia porri
fungus
Botrytis porri, Sclerotinia porri
China, Iran, Canada, Chile, Venezuela, Finland, Germany, Hungary, Norway, United Kingdom, Australia, New Zealand
CA, OR, NV, WA
Brazil, Mexico
2021-10-26 18:34:02
Botryotinia porri primarily spread by planting material (bulbs of garlic, possibly young seedlings of leek). Internationally, it could also be introduced into new areas with garlic bulbs or leeks for consumption, although it is relatively unlikely that diseased material should enter international trade because of its obvious poor quality.
onion, leek, garlic
No
BOTTPO-2,BOTTPO-3,BOTTPO-4,
Pathway not proven. Only one report of seed being a pathway for B. porri in onion (BOTTPO-2). Botryotinia porri is a pathogen of garlic and leek and is less important on onion.
BOTTPO-2,BOTTPO-3,BOTTPO-4,
Blotter incubation
BOTTPO-2,
This test has not been validated or standardized.
Good hygiene will prevent the persistence of sclerotia or infected crop debris in the soil. Agricultural practices that would create cool moist conditions in the upper layers of the soil should be avoided, in particular in relation to irrigation.
du Toit LJ, Derie ML, Hsiang T, Pelter GQ, 2002. Botrytis porri in onion seed crops and onion seed. Plant Disease, 86:1178.
du Toit LJ, Derie ML, and Pelter, GQ 2004, Prevalence of Botrytis spp. in Onion Seed Crops in the Columbia Basin of Washington.Plant Disease 88: 1061-1068
International Seed Federation Regulated Pest List Database. www.pestlist.worldseed.org. Nyon, switzerland
Pleospora herbarum
fungus
Too many to list, most commonly used names include Alternaria putrefaciens, Clasterosporium putrefaciens, Sporidesmium putrefaciens, Stemphyllium botryosum, Stemphylium herbarum.
Worldwide
Widespread
2023-08-21 16:43:10
Primarily a post harvest pathogen
Wide host range
No
PLEOHE-2,PLEOHE-4,
Pathway not proven. Some references indicate an association of Stemphylium botryosum spores with seed, however, no references found to indicate that seed is a proven pathway in onion.
PLEOHE-2,PLEOHE-4,
Stemphylium vesicarium
fungus
Pleospora alli, Helminthosporium vesicarium, Macrosporium alliorum, Mystrosporium alliorum, Macrosporium parasiticum, Stemphylium parasiticum
Worldwide
CA, FL, MI, NY, TX, WA
2021-04-27 18:09:21
Ascospores (P. allii) and conidia (S. vesicarium) are mainly air-dispersed. This pathogen is often referred to as Pleospora alli in the literature
onion, leek, alfalfa, wheat, sunflower, pea, radish, tomato, parsley
Yes
PLEOAL-8,PLEOAL-10,
Seed as a pathway is documented and accepted.
PLEOAL-8,PLEOAL-10,
Agar Incubation
PLEOAL-10,PLEOAL-12,
This test has not been validated or standardized
Seed treatments effective
PLEOAL-10,PLEOAL-12,
Jakhar SS, Suhag LS, Duhan JC, 1994. Prevalence and incidence of Stemphylium blight of onion (Allium cepa L.) and its management through cultural practices. Crop Research (Hisar), 8(3):562-564 (See CABI)
International Seed Federation Regulated Pest List Database. www.pestlist.worldseed.org. Nyon, switzerland
Aveling, T.A.S., Snyman, H.G. and Naude, S.P. (1993). Evaluation of seed treatments for reducing Alternaria porri and Stemphylium vesicarium on onion seed. Plant Disease, 77, 1009-1011.
Iris yellow spot virus
virus
Iris yellow spot tospovirus
Worldwide
AZ, CA, CO, GA, HI, ID
Korea
2022-03-22 18:09:05
Seed is not known to be a pathway for any host.
onion, leek, iris. Petunia, impatiens, rose, chrysanthemum and geranium reported as possible hosts especially when artificially inoculated.
No
IYSV00-1,ISF RPLD
Seed is not known to be a pathway. Iris yellow spot virus is not known to be a seed transmitted virus.
IYSV00-1,ISF RPLD
Xanthomonas axonopodis pv. allii
bacterium
Xanthomonas campestris pv. alli
Japan, Brazil, Venezuela, parts of Africa, Cuba, Barbados
CA, CO, GA, HI, TX
Korea
2021-05-18 20:10:13
onion, shallot, leek
Yes
XANTAA-2,XANTAA-4,
Seed is known to be a pathway.
XANTAA-2,XANTAA-4,
Seed wash/liquid plating, Bio-PCR
XANTAA-2,XANTAA-4,XANTAA-5,
Selective media and a BIO-PCR methods described. No validated or commercial seed assay available. PCR is an indirect way of testing (no isolation of the pathogen) and does not distinguish between viable and non-viable pathogen.
No seed treatments known to be effective
XANTAA-2,
A quality systems approach in production of the seeds by crop inspections should reduce the chances of this organism being associated with the seed.
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Roumagnac, P., Gagnevin, L., and Pruvost, O. 2000. Detection of Xanthomonas sp., the causal agent of onion bacterial blight, in onion seeds using a newly developed semi-selective isolation medium. Eur. J. Plant Pathol. 106:867-877.
Robene-Soustrade, I., Legrand, D., Gagnevin, L., Chiroleu, F., Laurent, A. and Pruvost, O. 2010. Multiplex nested PCR for detection of Xanthomonas axonopodis pv. allii from onion seeds. Applied and Environmental Microbiology, 76:2697-2703.
Fusarium redolens
fungus
Fusarium oxysporum var. redolens
China, Japan, Turkey, New Zealand, Czech Republic, Finland
Not known to occur
Korea
2021-04-07 16:27:34
No references found indicating seed is a pathway.
An economic pathogen of carnation. Though reported on other vegetable and grain crops, it is not considered an economic pathogen of many hosts or its economic importance is not known. Only hosts with peer reviewed publications are listed below. Other crops often listed in various countries harmful pest lists or inventories without evidence presented.
No
FUSARE-1,
No references found indicating seed is a pathway. Only one reference found indicating onion may be a host in Finland. Not considered an economic pathogen of onion.
FUSARE-1,
Fusarium redolens In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Phytophthora porri
fungus
Japan, South Africa, Canada, Europe, Australia
Not known to occur
2021-02-01 22:31:51
The report from WI, USA is actually Phytophthora brassicae (Farr and Rossman, 2018). Seed is not known to be a pathway. All reports of post harvest diseases in brassica probably due to Phytophthora brassiceae and not Phytophthora porri (Farr and Rossman, 2018). Lettuce was listed as a possible host, but no data found to confirm.
onion, leek.Reported as a post harvest disease in carrot.
No
PHYTPO-1,PHYTPO-2
Seed is not known to be a pathway for Phytophthora porri.
PHYTPO-1,PHYTPO-2
Setophoma terrestris
fungus
Pyrenochaeta terrestris, Phoma terrestris
Worldwide
Widespread
Korea
2021-04-22 16:18:49
Ubiquitous soil fungus. Often a secondary invader of plant roots when weakened by other pathogens.
Wide host range, though only producing symptoms and disease on onion, corn and rice.
No
PYRETE-3,PYRETE-4,
Seed is not known to be a pathway.
PYRETE-3,PYRETE-4,
International Seed Federation Regulated Pest List Database. www.pestlist.worldseed.org. Nyon, switzerland
Sumner, DR. 2008 Pink Root. In, Compendium of Onion and Garlic Diseases and Pests, Second Edition. Eds. Schwartz, HF and Mohan, SK., American Phytopathological Society, St. Paul, MN, USA
Cercospora duddiae
fungus
India, Indonesia, China, Thailand, Philippines, Barbados, Jamaica, Sub-Sahara Africa,
Not known to occur
Korea
2021-04-08 15:59:37
onion, garlic
No
No references found indicating that seed is a pathway. Infects primarily mature plants (CERCDU-3)
Tobacco rattle virus
virus
Aster ringspot virus, Belladonna mosaic virus,Paeony mosaic virus, Paeony ringspot virus,Peony mosaic virus, Peony ringspot virus,Potato corky ringspot virus, Potato stem mottle virus,Ratel virus, Spinach yellow mottle virus, Tabakmauche Virus, Tabakstreifen und Kra, Tobacco rattle tobravirus,Tulip white streak virus
Worldwide
Widespread
Korea
2021-04-22 17:52:01
Transmitted in nature primarily by trichodorus and paratrichodorus nematodes. Seed is only known to be a pathway in some weed species.
Extensive host range
Pathway not proven
TRV000-6,TRV000-1,
Seed from artificially inoculated plants were used in above reference. There were no other references found indicating seed is a pathway for tobacco rattle virus in nature.
TRV000-6,TRV000-1,
Hamed A.H., El-Banna M. Om-Hashem, Ghanem G.A., El- nagaar M.H., Shafie M.S., 2012. Isolation and identification of Tobacco rattle tobravirus affecting onion (Allium cepa L.) plants in Egypt. International Journal of Virology 8: 39-49.
Tobacco rattle virus. In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Pseudomonas syringae pv. syringae
bacterium
Many
Worldwide
Widespread
Thailand, China, Korea
2022-12-01 19:52:31
Seed is known to be a pathway on several crops. Thailand lists this pathogen as prohibited on corn. China lists this pathogen (Pseudomonas oryzicola) as prohibited on rice.
Wide host range. Important vegetable and agronomic crops listed below.
Not a host
PSDMSY-2,
No references found indicating onion is a host for this bacterium.
PSDMSY-2,
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon, Switzerland
Pythium vexans
fungus
Pythium complectens, Phytopythium vexans, Pythium allantocladon, Pythium ascophallon, Pythium piperinum, Ovatisporangium vexans, Pythium euthyphyphon, Pythium polycladon
Africa, Asia, Europe, Guatemala, Caribbean, Fiji, Papua New Guinea, Samoa, Solomon Islands, Argentina, Brazil, Venezuela, Chile, South Korea, New Zealand, Canada
HI, OK, CA, NC, MD, VA, DE, PA, NJ, WA, TN, LA, WI, IA
Korea
2023-08-21 16:48:58
Primarily affecting seedlings and roots and is transmitted mainly through infested soil. Seed is not known to be a pathway for any host. Zoospores of this fungus can swim in open water for a short distance. This pathogen has been reported in S. Korea. Korea lists this pathogen as Phytopythium vexans
Wide host range
No
PYTHVE-1,PYTHVE-3,PYTHVE-4,
Seed is not known to be a pathway for any host.
PYTHVE-1,PYTHVE-3,PYTHVE-4,
Pythium vexans In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Richardson MJ, 1990. An Annotated List of Seed-borne Disease. International Seed Testing Association, Zurich, Switzerland
International Seed Federation Regulated Pest List Database. www.pestlist.worldseed.org. Nyon, switzerland
Pratylenchus brachyurus
nematode
Anguillulina brachyura, Pratylenchus leiocephalus, Pratylenchus pratensis, Pratylenchus steineri, Tylenchus brachyurus
Worldwide
Widespread
Korea
2022-06-28 18:00:54
Seed is not known to be a pathway. Common in tropics (PRATBR-1)
Wide host range
Not a host
PRATBR-1,PRATBR-2,PRATBR-3,
Though listed as a possible host (PRATBR-2), no other reference lists onion as a host. Seed is not known to be a pathway for this nematode in any of its hosts.
PRATBR-1,PRATBR-2,PRATBR-3,
Ferris, H. 2019. Pratylenchus brachyurus. Nemaplex. www.nemaplex.ucdavis.edu.
Pratylenchus brachyurus. In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Phytophthora cinnamomi
fungus
Worldwide
Widespread
Korea
2021-05-03 18:40:42
This pathogen has been reported in Korea, Seed is not known to be a pathway.
Wide host range, primary trees and woody ornamentals
Not a host
Though ARS GRIN list onion as a potential host, no references were found confirming onion is a host.
Cladosporium cladosporioides
fungus
Cladosporium graminum, Cladosporium herbarumMycosphaerella schoenoprasi, Mycosphaerella tulasnei, Mycosphaerella tassiana, Penicillium cladosporioides,Hormodendrum cladosporioides, Monilia humicola
Worldwide
Widespread
Korea
2022-11-11 18:45:32
This pathogen is considered primarily a post harvest pathogen that does not cause disease in most of it's hosts (CLADCL-1). The fungus has been isolated from seed in some hosts, but does not transmit or cause disease in most cases.
Wide host range
No
CLADCL-1,
No references found indicating seed is a pathway. This fungus is primarily a post harvest fungus and field debris may provide survival habitat for the fungus.
CLADCL-1,
Cladosporium cladosporioides. In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Alternaria alternata
fungus
Alternaria tenuis, Alternaria tenuissima, many others
Worldwide
Widespread
Korea
2022-09-13 19:18:44
Korea listed this pathogen as Alternaria spp. A. alternata, A. tenuis and A. tenuissima have all been reported in Korea. A. alternata has often been found on seed in laboratory testing. There is little evidence of seed transmission. This fungus is ubiquitous and often of minor importance in its hosts.
Wide host range
No
ALTEAL-4,
No references found indicating seed is a pathway. Onion has been reported a host of the pathogen. This fungus is ubiquitous and found on many plant species.
ALTEAL-4,
Richardson MJ, 1990. An Annotated List of Seed-borne Disease. International Seed Testing Association, Zurich, Switzerland
Pantoea ananatis
bacterium
Bacillus ananas, Bacterium ananas, Chromobacterium ananas, Erwinia ananas pv. uredovora, Erwinia ananatis,Erwinia herbicola var. ananas, Erwinia urediniolytica,Erwinia uredovora, Pantoea ananas pv. ananas, Pantoea ananas pv. uredovora, Pantoea ananatis pv. ananatis,Pantoea ananatis pv. uredovora, Pectobacterium ananas, Pectobacterium ananatis pv. ananatis, Xanthomonas uredovora
Africa, Asia, Belgium, Italy, Russia, Poland, Spain, Nova Scotia, Mexico, Haiti, Puerto Rico, Guatemala, Australia, Argentina, Ecuador, Brazil, Guyana, Uruguay, Venezuela
CA, CO, FL, GA, MI, TX, NY
Chile
2023-07-28 19:23:26
Probably ubiquitous, causes post harvest rots in vegetables such as tomato, cantaloupe and some berries. Causes diseases in the field in the hosts listed below. Reported in host range studies on other Poaceae species. Most common in warm, wet climatic conditions.
onion, corn, rice, sudangrass, pineapple.
Yes
CABI CPC,ISF RPLD,ERWIAN-1,ERWIAN-2,ERWIAN-3,ERWIAN-4,ERWIAN-6,
Contamination of seed by this bacteria is well documented.
CABI CPC,ISF RPLD,ERWIAN-1,ERWIAN-2,ERWIAN-3,ERWIAN-4,ERWIAN-6,
PCR, Plating on semi-selective media
ISF RPLD,ERWIAN-4,ERWIAN-1,
Use of both methods suggested. These methods have not been standardized or validated.
CABI CPC,
Cultural practices to reduce this pathogen in weeds and thrips are suggested
Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
Walcott, RR, et.al. 2002. Natural infestation of onion seed by Pantoea ananatis, causal agent of center rot. Plant Disease, 86, 106-111.
Goszczynska, T., et.al. 2006. Isolation and identification of Pantoea ananatis from onion seed in South Africa. Seed Science and Technology 34: 655-668
Gent, DH and Schwartz, HF. 2008. Center Rot. In, Compendium of Onion and Garlic Diseases and Pests, Second Edition. Eds. Howard F. Schwartz and S. Krishna Mohan. American Phytopathological Society, St. Paul, MN, USA
Goszczynska, T, Venter, SN, Coutinho, TA. 2006. PA 20, a semi-selective medium for isolation and enumeration of Pantoea ananatis. Journ. of Microbiological Methods 64: 225-231
Khanal, M., Bhatta, B., & Malla, S. (2023). Isolation and characterization of bacteria associated with onion and first report of onion diseases caused by five bacterial pathogens in texas, u.s.a. Plant Disease, 107(6), 1721–1729
Shallot yellow stripe virus
virus
Welsh onion yellow stripe virus
Indonesia, China, Thailand
Not known to occur
Korea
2021-04-25 20:34:33
Aphid transmitted potyvirus. Potyviruses are not known to be seed transmitted. Phloem-limited
shallot, onion
No
No references found indicating seed is a pathway.
Erwinia rhapontici
bacteria
Aplanobacter rhapontici, Bacillus rhapontici, Bacterium rhapontici, Erwinia carotovora var. rhapontici, Pectobacterium rhapontici, Phytomonas rhapontici, Pseudobacterium rhapontici,Xanthomonas rhapontici
Asia, Europe, Canada, Mexico, New Zealand
Western and Midwest states
Brazil
2023-04-20 17:06:21
Brazil lists this as Pectobacterium rhapontici.
Primarily rhubarb and wheat. Reported on a few vegetables.
No
ISF RPLD,
This bacteria is a wound pathogen known to occur on onions. No references found indicating seed as a pathway in onion. Seed can be a pathway in peas and bean.
ISF RPLD,
International Seed Federation Regulated Pest List Database. pestlist.worldseed.org Nyon Switzerland
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