Medicago sativa
alfalfa
38 Related Pests
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
No references found indicating seed is a pathway. Alfalfa is not a common host for this virus.
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.
No
DITYDI-1,DITYDI-2,CABI CPC,
Pathway not proven. Research speculated seed transmission of Ditylenchus dipsaci in alfalfa based on field pattern, but live nematodes were not recovered from seed samples suspected of Ditylenchus dipsaci infestation. D. dipsaci is more commonly carried in plant debris associated with seed.
DITYDI-1,DITYDI-2,CABI CPC,
Sieve method
CABI CPC,
Used for research. This method has not been standardized or validated.
Fumigants (methyl idodide) Hot water treatments
CABI CPC,DITYDI-1,
Cleaning of seed effective in removing nematodes . Certification schemes also effective.
Neergaard, P. 1977. Seed Pathology Volume 1. McMillian Press, London, UK 839pp
Atkinson, H.J., Skyes, G.B.1981 An analysis from aerial photography of the spread of seed-borne Ditylenchus dipsaci in lucerne. Nematologica 27:235-241
Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Alfalfa mosaic virus
virus
Alfalfa virus 1 and 2, Lucerne mosaic virus, Marmor medicaginis, Potato calico virus, Tomato necrotic tip curl, Alfalfa yellow spot
Worldwide
Widespread
Sudan, Mexico
2022-09-13 19:10:36
Wide host range
Yes
AMV000-1,AMV000-2,
Seed borne AMV in alfalfa is established and accepted.
AMV000-1,AMV000-2,
Bioassay, ELISA, PCR
AMV000-2,AMV000-3,
Tests have not been standardized or verified
No
AMV000-1,
Use of virus-free seed, Vector aphid control. Some slight genetic resistance.
Alfalfa Mosaic Virus. In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Bailiss KW, Offei SK, 1990. Alfalfa mosaic virus in lucerne seed during seed maturation and storage, and in seedlings. Plant Pathology, 39(3):539-547
Bariana HS, Shannon AL, Chu PWG, Waterhouse PM, 1994. Detection of five seedborne legume viruses in one sensitive multiplex polymerase chain reaction test. Phytopathology, 84(10):1201-1205
Xanthomonas axonopodis pv. alfalfae
bacterium
Bacterium alfalfae, Phytomonas alfalfae, Pseudomonas alfalfae, Xanthomonas alfalfae, Xanthomonas campestris pv. alfalfae, Xanthomonas phaseoli f.sp. alfalfae
Widespread in Africa, Australia, Asia, USA and Europe.
Reported in IA, KS, WI, MD
Sudan
2022-10-09 00:32:24
The disease is present in Sudan.
Restricted to lucerne/alfalfa, in nature. Several other legumes are infected by artificial inoculation including Medicago truncatula, Medicago esculenta, Trifolium incartum, Lablab purpureus, Melilotus indica, Phaseolus vulgaris, Pisum sativum, Vicia benghalensis and Vigna mungo.
No
XANTAL-1,XANTAL-2,XANTAL-3,
The pathogen can survive for several years in hay or in debris with stored seed, allowing it to be transported to new areas. But clean seed is not a pathway.
XANTAL-1,XANTAL-2,XANTAL-3,
Xanthomonas axonopodis pv. alfalfae In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Claflin, L. E.; Stuteville, D. L. 1973. Survival of Xanthomonas alfalfae in alfalfa debris and soil. Plant Disease Reporter 57:52-53
Graham, J. H., Frosheiser, F. I., Stuteville, D. L., and Erwin, D. C. 1979. A Compendium of Alfalfa Diseases. The American Phytopathological Society, St. Paul, MN.
Clavibacter michiganensis subsp. insidiosus
bacterium
Aplanobacter insidiosus, Bacterium insidiosum, Burkholderiella insidiosa, Corynebacterium insidiosum, Corynebacterium michiganense pv. insidiosum, Corynebacterium michiganense subsp. insidiosum, Erwinia insidiosa, Mycobacterium insidiosum, Phytomonas insidiosa
Worldwide
AK,, CA, MD, MN, OK, OR
Sudan, China, Korea
2022-01-25 18:45:07
Currently absent from many EU countries, Canada and Brazil. Many countries report presence, but no significant disease.
Alfalfa, other forage Fabaceae spps., native and invasive clovers.
Yes
CORBIN-1,CORBIN-2,CORBIN-3,
Clavibacter michiganesis pv. insidiosus may be seed borne, but seed transmission under agronomic conditions is rare. Diseased plants generally produce relatively few seeds. The seeds which are produced are of low quality, usually shrunken and shriveled. These seeds are difficult to detect in large seed lots and are usually removed during the seed cleaning process.
CORBIN-1,CORBIN-2,CORBIN-3,
Culture plate, PCR
CORBIN-4,
These tests have not been standardized or validated. Culture plating is used by Canadian Food Inspection System.
CORBIN-1,
Resistant varieties are available.
Clavibacter michiganensis subsp. insidiosus In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Cormack MW, Moffatt JE, 1956. Occurrence of the bacterial wilt organism in alfalfa seed. Phytopathology, 46:407-409.
Samac, D. A.; Paul, S.; Nix, R. J.; Oleson, A. E. 1998 Transmission frequency of Clavibacter michiganensis subsp. insidiosus to alfalfa seed and identification of the bacterium by PCR. Plant Disease 82:1362-1367
Sheppard JW, 1991. Protocol sheet No. 14. Ottawa, Canada: Seed Borne Disease Unit, Central Seed Laboratory, Canadian Food Inspection System.
Rhodococcus fascians
bacterium
Corynebacterium fascians, Bacterium fascians, Phytomonas fascians, Pseudobacterium fascians, Rhodococcus rubropertinctus
Europe, North America, Central America, Australia, New Zealand, Iran, Russia, Egypt, Colombia
Widespread
Brazil, Thailand
2023-08-21 16:50:36
Though found in many US states, the pathogen is usually restricted and localized. Probably Worldwide, though not reported. Disease outbreaks are sporadic and usually related to poor sanitation. Bulbs, floral and greenhouse crops most susceptible to disease outbreaks. No reports of seed as a pathway in vegetables and agronomic crops.
Primarily a pest of ornamentals, woody ornamentals and floowers. Vegetables and agronomic crops reported susceptible to the bacterium are listed below. Transmits primarily through propagation.
No
CORBFA-3,
Listed as a potential host, no published references found to support. No references found indicating seed is a pathway.
CORBFA-3,
Putnam,M.L. and Miller, M.L. 2007. Rhodococcus facians in Herbaceous Perennials. Plant Disease 91: 1064-1076
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
Cuscuta spp.
parasitic plant
There are many speices of Cuscuta. Of primary concern in alfalfa, lucerne are Cuscuta campestris and Cuscuta epithymum/trifolia, Cuscuta indecorum, Cuscuta planifolia.
Worldwide. Cuscuta campestris has spread primarily from its native locations in the US and Cuscuta epithymum from its native locations in Asia
Widespread, essentially every state has reported dodders. Every state in the US lists Cuscuta as noxious and prohibited from movement. Cuscuta planifolia is not found in the US
Mexico
2022-02-16 19:09:52
Cuscuta spp. includes Cuscuta campestris, Cuscuta epithymum/trifolia, Cuscuta indecora, Cuscuta planifolia. Species tend to be host specific. Considered a noxious weed seed in many countries and US states (CUCCUTA-1)
Wide host range
Yes
CABI CPC,
Cuscuta seed may be a contaminant of the seed crop. It is not seed transmitted and is not parasitic on seed.
Physical purity
CABI CPC,
Physical purity by trained seed technologist
Certification of seed by AOSA or SCST or ISTA lab critical to prevention of movement and spread.
Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Aphelenchoides ritzemabosi
nematode
Aphelenchoides ribes, Aphelenchoides phyllophagus, Aphelenchoides ritzema-bosi, Pathophelenchus ritzemabosi, Pseudaphelenchoides ritzemabosi, Tylenchus ribes
Worldwide
CA, CO, WY, FL
China
2021-09-14 21:07:53
Has restricted distribution in China
Primary hosts are chrysanthemum and strawberry. Reported on a wide range of hosts, only important hosts listed below.
No
APLORI-1,APLORI-2,
No evidence that seed is a pathway. Only seed of Chinese aster a known pathway for this nematode (APLORI-1)
APLORI-1,APLORI-2,
Brown, 1956. A seed-borne attack of chrysanthemum eelworm (Aphelenchoides ritzema-bosi) on the annual aster (Callistephus chinensis). Journal of Helminthology, 30:145-148.
Aphelencoides ritzemabosi In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Phoma medicaginis var. medicaginis
fungus
Ascocyta imperfecta
Worldwide-temperate regions (Farr and Rossman, 2020)
Midwest states and CA
2022-08-10 16:31:51
alfalfa
Yes
PHOMME-2,PHOMME-3,PHOMME-4,PHOMME-5,PHOMME-6
Although these references indicate that the pathogen is commonly seedborne, they present minimal evidence of seed transmission. Most literature refers to the old name of Ascocyta imperfecta
PHOMME-2,PHOMME-3,PHOMME-4,PHOMME-5,PHOMME-6
Agar plating
PHOMME-4,PHOMME-5,
Method used experimentally only and has not been standardized or verified for clinical use.
PHOMME-5,
Weed control and burning eliminate overwintering on plant tops.
Neergaard, P. 1977. Seed Pathology Volume 1. McMillian Press, London, UK 839pp
Boerema, GH, et.al. 2004. Phoma Identification Manual. CABI Publishing, Wallingford, UK pp470
Mead and McCormack, 1961. Studies on Ascocyta imperfecta Peck. Parasitic strains among fifty isolates from Canadian alfalfa seed. Can J. Bot. 39:793-797
Kernkamp and Hendricks. 1953. The relationship of Ascocyta imperfecta to alfalfa seed production in Minnesota. Phytopathology 43:378-383
Farr, DF and Rossman AY 2015. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. http://nt.ars-grin.gov/fungaldatabases/
Verticillium nigrescens
fungus
China, Japan, Canada, Italy, Australia, New Zealand. (Most likely a worldwide saprophyte.)
GA, MS, MO
Brazil
2022-10-09 00:10:34
Not considered a highly virulent fungal pathogen. Often found as a saprophyte or weakly pathogenic at most. This fungus should not be regulated on seed.
Soybean and cotton are main hosts, but even on these hosts it is a weak pathogen. Has been isolated from other hosts, though primarily as a saprophyte or weakly pathogenic
No
No references found indicating seed is a pathway.. Reported as a weak pathogen on this host
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.
Yes
VERTAA-5,VERTAA-6,
Seed is known to be a pathway, though contamination is primarily external.
VERTAA-5,VERTAA-6,
Culture plating, Microscopic exam
VERTAA-5,VERTAA-6,VERTAA-7,
This method has not been validated or standardized.
Thiram has been used in Canada, but no data on success found. Â Storage of seed for 1 yr. may eliminate pathogen from the seed.
VERTAA-6,VERTAA-8,
Resistant varieites are known
Christen AA, 1983. Incidence of external seedborne Verticillium albo-atrum in commercial seed lots of alfalfa. Plant Disease, 67:17-18
Sheppard JW, Needham SN, 1980. Verticillium wilt of alfalfa in Canada: occurrence of seed-borne inoculum. Canadian Journal of Plant Pathology, 2:159-162
Christen AA, 1982. Demonstration of Verticillium albo-atrum within alfalfa seed. Phytopathology, 72:412-414
Huang HC, Kozub GC, Kokko EG, 1994. Survival of Verticillium albo-atrum in alfalfa seeds. Canadian Journal of Botany, 72:1121-1125
Verticillium dahliae
fungus
Verticillium ovatum, Verticillium trachiephilum
Worldwide
Widespread
China
2022-11-11 18:36:13
Prevalent in China
Wide host range (ornamentals, vegetables, agronomic). Isolated from some small grains but not pathogenic on small grains
No
VERTDA-16,VERTDA-18,
Pathway not proven. Verticillium wilt of alfalfa is primarily caused by Verticillium albo-atrum. Verticillium dahliae was isolated on seed, but these isolates were not pathogenic on alfalfa.
VERTDA-16,VERTDA-18,
Phytophthora medicaginis
fungus
Phytophthora megasperma, Phytophthora megasperma f.sp. medicaginis, Phytophthora sojae f.sp. medicaginis
Japan, Pakistan, Turkey, Argentina, S. Africa, Canada, Australia, Europe
Widespread
China
2022-06-27 17:07:24
This pathogen has not been reported in China
lucerne/alfalfa, chickpea
No
PHYTME-1,PHYTME-3,
No evidence that seed is a pathway for this pathogen
PHYTME-1,PHYTME-3,
Phoma pinodella
fungus
Phoma medicaginis var. pinodella,Ascochyta pinodella, Phoma trifolii; Peyronellaea pinodella
Worldwide
Widespread
China
2023-08-21 16:37:21
This pathogen has not been reported in China
Pea, soybean and alfalfa are the most important hosts. Has been reported on beet, lentils, cotton, parsley, fava bean, mung bean, cowpea, oats, barley, clovers and leguminous plants
No
PHOMMP-5,
Seed of other Medicago spp. may be a pathway, but no evidence of Medicago sativa seed as a pathway.
PHOMMP-5,
Mebalds MI, 1987. Mycoflora of Medicago truncatula, M. rugosa and M. littoralis seed produced in Victoria, Australia. Seed Science and Technology, 15:175-183
Phytoplasma australiense
fungus
Candidatus phytoplasma australiense, Phormium yellow leaf phytoplasma, Australian grapevine yellows phytoplasma, Pawpaw dieback phytoplasma. *Tran-Nguyen 2008
Australia, New Zealand
Not known to occur
China
2021-04-19 18:11:00
This pathogen has not been reported in China
Primarily grapevines, strawberry, alfalfa, pumpkin, giant pumpkin.
No
No references found indicating seed is a pathway. Alfalfa has been identified as a minor host of the pathogen.
Calonectria ilicicola
fungus
Cylindrocladium parasiticum, Calonectria theae var. crotalariae, Calonectria crotalariae, Cylindrocladium ilicicola
China, India, Indonesia, Iran, Japan, Republic of Korea, Malaysia, Taiwan, Thailand, Kenya, Brazil, Venezuela, Belgium, Ecuador, Italy, Netherlands, United Kingdom, Australia
FL, GA, HI, LA, MS, NC, SC, TX, VA, WV
China
2021-10-28 19:38:24
A major pathogen of avacado, peanut and eucalyptus. Reported in soybean, alfalfa
No
There is no evidence that seed is a pathway for this pathogen in this crop. No references found.
White clover mosaic virus
virus
Potexvirus
Western Australia. Possibly Japan, Turkey, Brazil, United Kingdom
IN
Brazil
2023-08-21 17:05:30
Primarily clover, pea, sweet pea, alfalfa. Artificially inoculated into other legumes and plant species in the laboratory. Only crops with reported natural infections of this virus included below.
No
WCLMV0-2,
Mechanically transmitted in laboratory studies. There is no evidence of that seed is a pathway for this host in nature.
WCLMV0-2,
Bancroft, Tuite & Hissong. 1960. Properties of White Clover Mosaic Virus in Indiana, Phytopathology 50: 711.
Xylella fastidiosa
bacterium
Worldwide
Widespread
China, Korea, Mexico
2022-10-11 01:20:02
Requires the sharpshooter leafhopper for transmission.
Primarily a pathogen of grapevines and stone fruits. Other trees, fruit crops, ornamentals and flowers have been reported as hosts. The bacterium is also known to survive in many Poaceae grasses. Vegetables and small grains are not known to be hosts.
No
XYLEFA-1,XYLEFA-4,
Seed is not known to be a pathway in alfalfa seeds. No references found indicating Xylella fastidiosa infects alfalfa in nature.
XYLEFA-1,XYLEFA-4,
Pea enation mosaic virus-1
virus
Pea enation mosaic, Pea virus 1, Pea enation mosaic penamovirus, Pea enation mosaic virus 'group'
Probably worldwide, primarily northern temperate climates.
Probably all pea growing regions.
Mexico
2022-05-12 18:52:21
Though found in most pea production areas, this virus is not common. Recent data indicates that both PEMV-1 and PEMV-2 are needed to cause disease in its hosts (DVP Web #372)
pea, faba bean, alfalfa
No
No references found indicating seed is a pathway. Alfalfa may is an uncommon host.
Streptomyces scabiei, Streptomyces ipomoceae, Streptomyces acidiscabies, Streptomyces stelliscabiei
bacterium
Streptomyces scabiei is worldwide, other Streptomycese spp. are more localized.
Streptomyces cabiei is widespread in the United States, other Streptomyces spp. are more localized.
Sudan
2022-09-13 18:33:51
There are many beneficial Streptomyces spp. that suppress pathogens or enhance nodulation in alfalfa. There are no known Streptomyces pathogens of alfalfa. No reports of any Streptomyces in Sudan
Streptomyces scabiei is primarily a pest of potato, but is found on other root crops such as carrot, parsnip, radish and beet. Streptomyces ipoomceae is a pathogen of sweet potato, only. Streptomyces acidiscabies and Streptomyces stelliscabiei are pests of potato only. There are no known Streptomyces pathogens of alfalfa. Only hosts of Streptomyces scabiei reported below.
No
Not a host. There are no reports of any pathogenic Streptomyces on alfalfa
Fusarium oxysporum f.sp. medicaginis
fungus
Fusarium medicaginis
Asia, North America, South America, Europe
AL, AZ, CA, CO, IL, IA, KS, MD, MN, MS, MT, NE, NC, OR, PA
Sudan
2021-04-14 21:37:49
alfalfa
No
FUSAMD-3,FUSAMD-1,FUSAMD-2,
Seed pathway speculated in one reference (FUSAMD-2) but no evidence presented to prove seed is a pathway. Other references listed do not indicate that seed is a pathway for this pathogen.
FUSAMD-3,FUSAMD-1,FUSAMD-2,
Richardson, 1990. An Annotated List of Seed-borne Diseases. International Seed Testing Association, Zurich, Switzerland.
Fusarium oxysporum f.sp. medicaginis In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc."
Neergaard, P. 1977. Seed Pathology Volume 1. McMillian Press, London, UK 839pp
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-6,PLEOHE-7,PLEOHE-16,
Pathway not proven. All three references only show that the pathogen can infect seed and recovered later in laboratory assays. No data on seed transmission found or seed being a pathway in nature. Infected seed is usually smaller than healthy.
Freezing blotter incubation
PLEOHE-6,PLEOHE-7,PLEOHE-16,
Blotter assay, Grow out
PLEOHE-15,
Standard blotter or freezing blotter are methods used by ISTA. No evidence of seed transmission.
Conditioning seed for removal of small sizes may help reduce seed lot contamination
Al-Askar AAA, Ghoneem KM, Rashad YM, 2012. Seed-borne mycoflora of alfalfa (Medicago sativa L.) in the Riyadh region of Saudi Arabia. Annals of Microbiology, 62:273-281
Susuri LR, Doda-Gashi N, 2003. Alfalfa seed microflora and some characteristics of obtained isolates. (Mikroflora sjemena lucerne i neke karakteristike dobiveneh izolata.) Fragmenta Phytomedica et Herbologica, 28:81-88.
Neslon, RR, 1955. Stemphyllium Leafspot on Alfalfa. Phytopathology 45:352-356
International Seed Testing Association (1999) International rules for seed testing. Seed Sci Technol 24:1–35
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
No
PLEOAL-9,
Pathway not proven. Only one reference found indicating that seed may be a pathway. This pathogen has only been reported on alfalfa in South Africa and Australia.
PLEOAL-9,
Hot water and sodium hypochloride followed by thiram effectiveÂ
PLEOAL-9,
Lamprecht SC, Knox-Davies PS, 1984. Stemphylium vesicarium on lucerne (Medicago sativa) seeds in South Africa. Phytophylactica, 16(3):189-19
Colletotrichum trifolii
fungus
Worldwide
Widespread
Sudan
2021-04-08 16:54:06
alfalfa, soybean, adzuki bean
No
COLLTF-4,COLLTF-5,
No evidence found indicating seed is a pathway. Richardson (COLLTF-5) lists seed as a potential source and cites Lamprecht, et. al.(COLLTF-4), however, this article does not include Medicago sativa in the research.
COLLTF-4,COLLTF-5,
Sclerotinia trifoliorum
fungus
Sclerotinia ciborioide, Sclerotinia trifoliorum var. trifoliorum, Sclerotinia bryophila
Worldwide
Widespread
Mexico
2021-04-27 17:13:36
alfalfa, clover
No
SCLETR-3,RICH ISTA,
Pathway not proven. Several references implied that seed may be a pathway, but no evidence was reported. Seed is a pathway in clover and it maybe inferred that alfalfa seed is also a pathway. References above only list clover seed as a potential pathway.
SCLETR-3,RICH ISTA,
Aphanomyces euteiches
fungus
Worldwide
Widespread
Mexico
2021-03-29 18:36:45
Not known to be seed transmitted. (APHAEU-1)
alfalfa, lucerne, beans, pea, lentil, faba bean, clover
No
APHAEU-1,
Seed is not known to be a pathway for this pathogen
APHAEU-1,
Aphanomyces euteiches In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Physoderma alfalfae
fungus
Cladochytrium alfalfae, Urophlyctis alfalfae
Worldwide
AL,CA, WA, MS, IN, MT, PA, TX
Korea
2021-04-15 13:48:19
A Chytrid fungi with mobile zoospores. Primarily soil borne in wet soils.
alfalfa, other Medicago spp.
No
PHYDAL-2,
No references found indicating seed is a pathway. Not listed in reference above. Primarily soil borne
PHYDAL-2,
Resistant varieties have been developed.
Richardson MJ, 1990. An Annotated List of Seed-borne Disease. International Seed Testing Association, Zurich, Switzerland
Cercospora medicaginis
fungus
Cercospora apii
Africa, Greece, Brazil, Cuba, Dominican Republic, Guatemala, India, China, Bulgaria, Uzbekistan, El Salvador,France, Philippines, Poland; Venezuela,
MS, TX, AL, KS, FL, GA, IA, NC, SD, WI,WV
Sudan
2021-04-08 16:05:38
alfalfa, lucerne, clover
No
No references found indicating that seed is a pathway for this fungus.
Didymella rabiei
fungus
Ascochyta rabiei, Mycosphaerella rabiei, Phyllosticta cicerina, Phyllosticta rabiei, Zythia rabiei
Worldwide
CA, ID, NE, ND, SD, WA
Korea
2021-04-13 17:14:48
The pathogen is also soil borne.
Primarily a pathogen of chickpea, though pea, alfalfa and cowpea can be hosts.
No
Though alfalfa can be a host for the pathogen, it is not considered to be an important host or an important disease of alfalfa. No references found indicating that alfalfa seed is a pathway.
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,
Seed is not known to be a pathway for any host.
PYTHVE-1,PYTHVE-3,
Pseudopeziza medicaginis
fungus
Phacidium medicaginis, Peziza medicaginis, Pseudopeziza medicaginis f.sp. medicaginis-sativae,Pseudopeziza trifolii f.sp. medicaginis-sativae
Worldwide
Widespread
Korea
2021-04-19 19:03:09
alfalfa, red clover, hairy vetch
No
No references found indicating seed is a pathway. Primary inoculum from debris in field (PSPZME-2).
Meloidogyne chitwoodi
nematode
Mozambique, South Africa, Belgium, Turkey, France, Germany, Italy, Netherlands, Portugal, Sweden, Canada, Mexico, Argentina
CA, CO, ID, NV, MN, OR, WA, TX, UT, VA, WY
Korea
2021-04-26 18:30:50
Seed is not known to be a pathway for Meloidogyne spp. root knot nematodes (MELGCH-2)
potato primarily, alfalfa, carrot, tomato, Poeaceae grasses. In greenhouse studies: pea, corn, wheat, barley, oat and sugarbeet.
No
MELGCH-1,MELGCH-2,
Seed is not known to be a pathway.
MELGCH-1,MELGCH-2,
Meloidogyne chitwoodii. In: Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
Lammers, W., Karssen, G., Jellema, P., Baker, R., Hockland, S., Fleming, C. and Turner, S. (2006). Meloidogyne minor Pest Risk Assessment. 08-14648 PPM Point 7.3. Plant Protection Services (NL) and Central Science Laboratory (UK). 52pp. (https://www.eppo.int...)
Rhizoctonia leguminicola
fungus
Slafractonia leguminicola
Canada
WV, KY, WI, GA, IL, DE
Korea
2021-04-27 16:16:07
Produces toxins that are poisonous to livestock. Pathogen and distribution Information from ARS GRIN and RHZLEG-3
Alfalfa, red clover
No
RHZLEG-2,
Pathway not proven. Although a seed pathway has been indicated and seed certification was suggested as a valid management strategy, no research was presented. Seed is a pathway in red clover (RHZLEG-3) but this research on seed transmission did not include alfalfa.
RHZLEG-2,
RHZLEG-2,
Rhodes, LH and Gerkin DK. 2016. Blackpatch. In, Compendium of Alfalfa Diseases and Pests, Third Edition. Samac, DA, Rhodes, LH and Lamp, WO, eds. The APS Press, St. Paul, MN, USA
Leptosphaeria pratensis
fungus
Phloeospora trifolii, Phoma melilothi,Stagnospora compta, Stagonospora medicaginis,Stagonospora meliloti, Stagonospora trifolii, Leptosphaeria weimeri
Australia, New Zealand, France, Sweden, Canada, United Kingdom
Widespread
Korea
2021-04-26 17:47:53
Korea lists this pathogen as only Leptosphaeria spp.
alfalfa, clover
No
STAGME-3,
No references found indicating seed is a pathway. Primarily borne in plant debris and spread by splashing rain/irrigation.
STAGME-3,
Irwin, JAG and Amour, DJ. 2015. Stagnospora Leaf Spot and Root Rot. In, Compendium of Alfalfa Diseases and Pests, 3rd. ed. Samac DA, Rhodes LH and Lamp WO, eds. The American Phytopathological Society, St. Paul, MN, USA
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,ALTEAL-31,
A. alternata has been reported on alfalfa but it is considered a saprophyte of alfalfa. A. alternata has been found on seed, in laboratory surveys but, no references were found indicating seed transmission.
ALTEAL-4,ALTEAL-31,
Blotter incubation
ALTEAL-31,
Blotter incubation was used in surveys. This method has not been standardized or validated.
Richardson MJ, 1990. An Annotated List of Seed-borne Disease. International Seed Testing Association, Zurich, Switzerland
Al-Askar, AA.A., Ghoneem, K.M. & Rashad, Y.M. 2012. Seed-borne mycoflora of alfalfa (Medicago sativa L.) in the Riyadh Region of Saudi Arabia. Ann Microbiol 62, 273–281.
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
Alfalfa (lucerne) has been reported as a host, though it may be uncommon. No references found indicating seed may be a pathway.
Peanut stunt virus
virus
black locust true mosaic virus, clover blotch virus, groundnut stunt virus, peanut common mosaic virus, peanut stunt cucumovirus, robinia mosaic virus
Morocco, Sudan, Asia, Bulgaria, France, Hungary, Italy, Poland, Spain
Southeast, Midwest states, WA
Brazil
2023-04-05 20:20:40
Common virus in peanuts. Can be seedborne in peanuts at low levels.
Primarily a virus of Fabaceae family, tomato, celery,
No
CABI CPC,
Alfalfa is not commonly known as a host of PSV. No references found indicating seed is a pathway.
CABI CPC,
Crop Protection Compendium. Wallingford, UK: CAB International. www.cabi.org/cpc.
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