Alternaria porri

fungus

Macrosporium porri, Alternaria allii

Worldwide

Widespread

Chile

2024-06-08

Purple blotch is most severe in hot humid onion climates. Has not been reported in Chile

Allium spp.

Yes

ALTEPO-5,ALTEPO-6,CABI CPC

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-5,ALTEPO-6,CABI CPC

Agar plating

ALTEPO-5,NSHS USDA

Agar Plating is s standard method of the NSHS

Chemical

ALTEPO-3,ALTEPO-5

Chemical seed treatments and disinfestation methods like hot water are possible but may be phytotoxic; however, newer seed treatment chemicals may be available, so it's advisable to consult with companies supplying these treatments.

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

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,

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

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,

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

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.

Burkholderia gladioli pv. allicola

bacterium

Phytomonas allicola, Pseudomonas allicola, Pseudomonas gladioli pv allicola

Asia: Israel; Europe: Slovenia; Oceania: Australia, New Zealand; South America: Brazil.

Not known to occur

China, Korea

2024-11-09

Primarily isolated from soil or wet onion residues.

The only natural host is onion. Artifical inoculation includes iris, tulip, narcissus and carrot

No

PSDMGA-3,ISF RPLD

No references found indicating seed as a pathway for this pathogen.

PSDMGA-3,ISF RPLD

Candidatus phytoplasma asteris

phytoplasma

Aconitum proliferation, Aconitum virescence, Alberta aster yellows, alfalfa stunt, Alstroemeria decline, American aster yellows, Anemone virescence, apple sessile leaf, apricot chlorotic leaf roll, azalea little leaf, banana elephantiasis, basil little leaf, Bermuda grass white leaf, black currant reversion, black pepper yellows, blueberry stunt, broccoli phyllody, Bunias phyllody, cactus virescence, cactus witches'-broom, Calendula virescence, canola yellows, Cardaria phyllody, carrot proliferation, carrot yellows, cassava phyllody phytoplasma, cassava witches' broom, Catharanthus little leaf, Catharanthus virescence, chayote witches'-broom, cherry bunch leaf, cherry little leaf, chlorantie, Chrysanthemum witches'-broom, Chrysanthemum yellows, Cirsium stunt, Cirsium yellows, clover phyllody, columbine virescence, coorg black pepper yellows, cosmos phyllody, Cyclamen virescence, dandelion yellows, Delphinium virescence, dill yellows, Diplotaxis virescence, dogfennel yellows, dogwood stunt, dwarf western aster yellows, eastern aster yellows, Echinacea phyllody, eggplant dwarf, eggplant little leaf, Epilobium phyllody, Erigeron yellows, European aster yellows, false ragweed, Festuca yellows, Gaillardia yellows, Gladiolus virescence, grapevine yellows, grey dogwood stunt, hyacinth yellows, Hydrangea phyllody and virescence, Ipomoea obscura witches' broom, Italian cabbage yellows, Italian lettuce yellows, kale phyllody, larkspur virescence, lazy daisy yellows, lettuce yellows, lilac little leaf, Limonium proliferation, Limonium yellows, Lotus yellows, maize bushy stunt, mallow yellows, marguerite yellows, marigold phyllody, marigold virescence, Maryland aster yellows, Mitsuba witches' broom, monarda yellows, mulberry dwarf, multiplier disease, New England aster yellows, New Jersey aster yellows, oat proliferation, Oenothera virescence, olive witches'-broom, onion phyllody, onion virescence, onion yellows, Papaver virescence, parsley yellows, Paulownia witches' broom, peach red leaf disease, pear proliferation and decline, periwinkle little leaf, periwinkle witches' broom and virescence, periwinkle yellows, Phytoplasma asteris, plantain virescence, Poa stunt, poplar witches' broom, poplar yellows, Portulaca yellows, potato purple top, prickly lettuce yellows, Primula yellows, pumpkin yellows, purple coneflower yellows, Quercus proliferation, ragweed yellows, Ranunculus phyllody, rape phyllody, rape virescence, rose witches'-broom, ryegrass yellows, safflower phyllody, Salix proliferation, sandal spike, Saponaria proliferation, Schizanthus proliferation, severe western aster yellows, soybean purple stem, Spirea stunt, Stellaria yellows, strawberry green petal, strawberry phylloid fruit, strawberry stunting, Symphytum proliferation, Tacaco witches'-broom, Tagetes witches' broom, Thalictrum proliferation, tomato big bud, tomato yellows, turnip virescence, Veronica phyllody, watercress witches'-broom, western aster yellows, wild radish yellows

Worldwide

Widespread

-

2024-11-09

Candidatus Phytoplasma asteris is naturally transmitted by a wide range of leafhopper, Macrosteles fascifrons is reported to be the principal vector. Seed is not a pathway.

Wide host range, primarily herbaceous dicots, though strains infect monocots and woody ornamentals

No

CABI CPC,ISF RPLD

Seed is not a known pathway.

CABI CPC,ISF RPLD

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

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,

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

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,

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

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.

Tomato ringspot virus

virus

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, tomato ringspot nepovirus, ToRSV, winter peach mosaic virus

Africa: Egypt, Nigeria, Togo; Asia: China, India, Iran, Japan, Jodan, Lebanon, Oman, Pakistan, South Korea, Taiwan, Turkey; Europe: Belarus, Croatia, France, Netherlands, Poland, Russia, Slovakia, Spain, UK; North America: Canada, Puerto Rico, USA; Oceania: Fiji, New Zealand; South America: Brazil, Chile, Colombia, Peru, Venezuela.

Widespread

Korea, Mexico, Thailand

2022-11-07

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 and berries. 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,

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

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

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

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.

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

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

AZ, CA, FL, MI, MN, NM, NY, TX, WA

-

2024-10-22

Ascospores (P. allii) and conidia (S. vesicarium) are mainly wind-blown or water-dispersed.

Main: onion, garlic, asparagus, soybean, alfalfa, tomato; Other: leek, sunflower, lettuce, radish.

Yes

PLEOAL-10,PLEOAL-8,CABI CPC

Seed as a pathway is documented and accepted. It is more severe under warm and moist conditions.

PLEOAL-10,PLEOAL-8,CABI CPC

Agar Incubation

PLEOAL-10,PLEOAL-12,NSHS USDA

This test has not been validated or standardized

Cultural, Chemical

PLEOAL-10,PLEOAL-12

Early detection is possible by trapping air-born conidia using spore traps. Remove or bury plant debris to reduce primary inoculum. Allow adequate airflow, avoid long periods of leaf wetness, reduce plant density, and include good drainage. Seed treatments effective.

Iris yellow spot virus

virus

Iris yellow spot tospovirus

Worldwide

AZ, CA, CO, GA, HI, ID

Korea

2022-03-22

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

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.

Fusarium redolens

fungus

Fusarium oxysporum var. redolens, Fusarium redolens var. solani, Fusarium solani var. redolens

Africa: Algeria, Tunisia; Asia: China, Iran, Japan, Pakistan, Turkey; Europe: Czechia, Finland, Netherlands, Poland, Sweden, UK; North America: Canada, USA,; Oceania: New Zealand.

MT, ND.

Korea

2024-09-04

No references found indicating seed is a pathway. Fusarium redolens is soil-borne.

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.

No

CABI CPC

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.

CABI CPC

Phytophthora porri

fungus

Africa: South Africa, Asia: Japan, Europe: widespread, Canada, Australia

None. The report from WI, USA is actually Phytophthora brassicae (USDA FD).

2024-05-04

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-2,CABI CPC

Seed is not known to be a pathway for Phytophthora porri.

PHYTPO-2,CABI CPC

Setophoma terrestris

fungus

Pyrenochaeta terrestris, Phoma terrestris

Africa: Senegal; Asia: India, Israel; Europe: Greece, Netherlands, Poland; North America: Mexico, USA; Oceania: Australia; South America: Argentina, Venezuela.

DE, IA, MD, VA.

Korea

2024-09-24

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-4,ISF RPLD,PYRETE-5

Seed is not known to be a pathway.

PYRETE-4,ISF RPLD,PYRETE-5

Cercospora duddiae

fungus

India, Indonesia, China, Thailand, Philippines, Barbados, Jamaica, Sub-Sahara Africa,

Not known to occur

Korea

2021-04-08

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

AK, CA, CO, FL, ID, IL, IN, MA, MI, MN, NE, NC, ND, OH, OR, PA, UT, WA, WI

Korea

2024-09-08

Tobacco Rattle Virus is soil-borne and transmitted between plants by the nematode species Trichodorus and Paratrichodorus. Seed is only known to be a pathway in some weed species.

TRV occurs on numerous crops in many countries and has been detected on over 100 mono- and dicotyledonous plant species.

Pathway not proven

TRV000-6,CABI CPC

One reference found indicating seed transmission via mechanical inoculation. There were no other references found indicating seed is a pathway for tobacco rattle virus in nature.

TRV000-6,CABI CPC

Pseudomonas syringae pv. syringae

bacterium

Many

Worldwide

Widespread

Thailand, China, Korea

2022-12-01

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,

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

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,

Pratylenchus brachyurus

nematode

Anguillulina brachyura, Pratylenchus leiocephalus, Pratylenchus pratensis, Pratylenchus steineri, Tylenchus brachyurus

Worldwide

Widespread

Korea

2022-06-28

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,

Phytophthora cinnamomi

fungus

Worldwide

Widespread

Korea

2021-05-03

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

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,

Alternaria alternata

fungus

Alternaria tenuis, Alternaria tenuissima, many others

Worldwide

Widespread

Korea

2022-09-13

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,

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

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

Shallot yellow stripe virus

virus

Welsh onion yellow stripe virus

Indonesia, China, Thailand

Not known to occur

Korea

2021-04-25

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

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,

Ditylenchus destructor

nematode

-

Africa: Nigeria, South Africa; Asia: Azerbaijan, China, Iran, Japan, Pakistan, Saudi Arabia, South Korea, Syria, Tajikistan, Turkey, Uzbekistan; Europe: Albania, Austria, Belarus, Bulgaria, Czechia, Estonia, France, Greece, Hungary, Ireland, Jersey, Latvia, Luxemburg, Moldova, Netherlands, Norway, Poland, Romania, Russia, Slovakia, Sweden, Switzerland, Ukraine, UK; North America: Canada, USA; Oceania: New Zealand.

CA, HI, ID, OR, SC, WA, WI

-

2024-09-26

Ditylenchus destructor is spread through seed potatoes. It is also spread on containers, packaging, and soil. True seed is not know to be a pathway.

Extensive host range. Main: ornamental bulbs, sweet potato, onion, garlic, groundnut, beet, sugarbeet, pepper, cucumber, pumpkin, carrot, soybean, tomato, potato, clover, wheat, corn

No

CABI CPC,ISF RPLD,EPPO,DITYDE-1

Seed is not a known pathway.

CABI CPC,ISF RPLD,EPPO,DITYDE-1