Plant pathogens montage

Plant Pathogens

Plant diseases can be caused by several pathogenic microorganisms including fungi, bacteria, viruses, viroids, phytoplasmas and plant parasitic nematodes. In California, several plant pathogens have evolved with native plants and consequently, caused little damage. However, many other pathogens are either not present or have only been newly discovered within the State. Without effective regulations in place, exotic pathogens may gain entry into California from other global regions through imported contaminated plant and soil commodities, and detrimentally impact the State’s agriculture and natural environments.


PEST RATING PROPOSALS:  

BACTERIA:  

Pseudomonas cichorii (Swingle 1925) Stapp 1928 Bacterial blight of endive Varnish spot of lettuce
Current Pest Rating: C
Proposed Pest Rating: C
Comment Period: 07/19/2021 through 09/02/2021

Spiroplasma citri Saglio et al.,1973 Stubborn disease of citrus
Current Pest Rating: none
Proposed Pest Rating: A
Comment Period: 06/21/2021 through 08/05/2021

Xanthomonas campestris pv. armoraciae (McCulloch) Dye 1978 Bacterial leaf spot of crucifers
Current Pest Rating: Z
Proposed Pest Rating: C
Comment Period: 07/12/2021 through 08/26/2021

FUNGI: 

Alternaria arborescens E.G. Simmons 1999
Current Pest Rating: Z
Proposed Pest Rating: C
Comment Period: 06/10/2021 through 07/25/2021

Colletotrichum alienum B. Weir & P.R. Johnst. 2012
Current Pest Rating: Q
Proposed Pest Rating: B
Comment Period: 06/10/2021 through 07/25/2021 

Colletotrichum fioriniae (Marcelino & Gouli) Pennycook 2017 Anthracnose Fruit and Crown Rot of Strawberry
Current Pest Rating: B
Proposed Pest Rating: C
Comment Period: 07/02/2021 through 08/16/2021

VIRUSES and VIROIDS:  

Avocado sunblotch viroid
Current Pest Rating: C
Proposed Pest Rating: C
Comment Period: 07/12/2021 through 08/26/2021

BACTERIA:

Acidovorax citrulli
Pest Rating:  A 

Allorhizobium vitis (Ophel and Kerr 1990) Mousavi et al. 2016 Crown gall of grapevine
Pest Rating: C

Clavibacter michiganensis corrig. (Smith 1910) Davis et al. 1984 emend. Nouioui et al. 2018 Bacterial canker of tomato
Pest Rating: B

Candidatus Liberibacter solanacearum
Pest Rating: B

Dickeya chrysanthemi (Burkholder et al., 1953) Samson et al., 2005 Bacterial wilt 
Pest Rating: C

Dickeya  fangzhongdai Tian, Zhao, Yuan, Yi, Fan, Xu, Hu, de Boer & Li 2016
Pest Rating: B

Erwinia amylovora (Burrill 1882) Winslow et al. 1920 Fire blight 
Pest Rating: C

Erwinia aphidicola
Pest Rating: B

Erwinia persicina corrig. Hao et al. 1990 
Pest Rating: B

Erwinia rhapontici (Millard 1924) Burkholder 1948
Pest Rating: B

Erwinia tracheiphila (Smith 1895) Bergey et al. 1923
Pest Rating: B 

Lelliottia amnigena (lzard et al. 1981) Brady et al. 2013
Pest Rating: Q
 

Pectobacterium atrosepticum (van Hall) Gardan et al. 2003 Blackleg of potato
Pest Rating: C 

Pectobacterium brasiliense (Portier et al. 2019) backleg disease of potato; soft rot of potato
Pest Rating: B

Pectobacterium carotovorum (Waldee 1945) Hauben et al. 1998 Bacterial soft rot
Pest Rating: C

Pseudomonas savastanoi pv. phaeolicola (Burkholder 1926) Gardan et al. 1992
Pest Rating: B

Pseudomonas mediterranea Catara, Sutra, Morineau, Achouak, Christen, & Gardan 2002 
Pest Rating: B

Pseudomonas savastanoi pv. glycinea (Coerper 1919) Gardan et al. 1992 Bacterial blight of soybean
Pest Rating: C

Pseudomonas syringae pv. actinidifoliorum(Van Hall, 1904) Cunty et al., 2014 Bacterial spot of Kiwifruit
Pest Rating: C

Pseudomonas syringae pv. hibisci (ex Jones et al. 1986) Young et al. 1991
Pest Rating: C 

Pseudomonas syringae pv. lachrymans (Smith & Bryan 1015) Young et al. 1978 Cucurbit angular leafspot
Pest Rating: B

Pseudomonas syringae pv. pisi (Sackett 1916) Young et al. 1978 Bacterial blight of pea
Pest Rating: C

 Pseudomonas syringae pv. syringae van Hall 1902 Bacterial canker and blast of stone and pome fruits & bacterial brown spot of beans
Pest Rating: C

Pseudomonas syringae pv. tomato (Okabe) Young, Dye & Wilkie 1978 Bacterial speck of tomato
Pest Rating: C

Ralstonia solanacearum Race 3 biovar 2 (Smith 1896) Young et al. 1996 Brown rot of potato/ Southern wilt of geranium
Pest Rating: A

Rhizobium radiobacter (Beijerinck & van Delden 1902) Young et al. 2001 Crown gall
Pest Rating: C

Rhodococcus fascians
Pest Rating:  C

Streptomyces scabiei(ex Thaxter 1892) Lambert & Loria, 1989
Pest Rating:  C

Xanthomonas arboricola pv. pruni
Pest Rating:  B

Xanthomonas campestris pv. campestris (Pammel 1895) Dowson 1939
Pest Rating:  B

Xanthomonas campestris pv. fici (Cavara 1905) Dye 1978 Leafspot and dieback of fig 
Pest Rating:  B 

Xanthomonas citri ssp. citri (Hasse, 1915) Constantin, Cleenwerck, Maes, Baeyen, Van Malderghem, De Vos, Cottyn 2016 Asiatic citrus canker
Pest Rating: A

Xanthomonas dyei Young et al., 2010
Pest Rating:  C

Xylella fastidiosa subsp. pauca (Wells et al., 1987) Schaad et al. 2004
Pest Rating:  A

Xanthomonas hortorum pv. pelargonii (Brown 1923) Vauterin et al. 1995 Bacterial blight of geranium
Pest Rating:  C

Xanthomonas vesicatoria (Doidge) Dowson 1939 (Bacterial spot of tomato and pepper)
Pest Rating: C

FUNGI:

Alternaria crassa (Sacc.) Rands 1917
Pest Rating: C  

Ascochyta aquileqiae
Pest Rating: C

Botrytis cinerea Pers. (1794) gray mold
Pest Rating: C

Calonectria pseudonaviculata 
Pest Rating:  B

Calonectria pteridis
Pest Rating: B 

Campylocarpon fasciculare Schroers, Halleen & Crous 2004 Black foot disease
Pest Rating: C

Ceratobasidium cereale D. Murray & L. L. Burpee 1984 Yellow patch of turfgrass/sharp eye spot of cereals
Pest Rating: C

Cercospora coniogrammes
 Pest Rating:  B

Cercospora insulana Sacc. 1915
Pest Rating: C

Cercospora ruscicola
Pest Rating: B

Chrysanthemum white rust | Puccinia horiana (Hennings 1901)
Pest Rating: A

Coleophoma empetri
Pest Rating: B

Coleosporium montanum (Arthur & F. Kern) Mctaggart & Aime 2018 Pine needle rust/ Solidago rust
Pest Rating: C  

Coleosporium plumeriae Pat. 1902 Plumeria rust
Pest Rating: C

Coleosporium solidaginis (Schwein.) Thüm. 1878 Pine needle rust/ Solidago rust
Pest Rating: C

Colletotrichum acutatum Simmonds ex Simmonds 1968 Black spot of strawberry
 Pest Rating: C

Colletotrichum aotearoa B. Weir & P.R. Johnst. 2012
 Pest Rating: B

Colletotrichum aracearum
Pest Rating: B

Colletotrichum asianum
Pest Rating: B

Colletotrichum boninense 
Pest Rating: B

Colletotrichum circinans (Berk.) Voglino 1921 onion smudge
Pest Rating: C

Colletotrichum cliviae
Pest Rating: B

Colletotrichum cordylinicola
Pest Rating: B

Colletotrichum cymbidiicola
Pest Rating: B

Colletotrichum fioriniae (Marcelino & Gouli) Pennycook 2017
Pest Rating: B

Colletotrichum fructicola
Pest Rating: B

Colletotrichum gloeosporioides (Penzig) Penzig & Saccardo 1882
Pest Rating: C

Colletotrichum godetiae Neerg. 1950 Apple bitter rot; Anthracnose of avocado
Pest Rating: B

Colletotrichum grevilleae F. Liu, Damm, L. Cai & Crous 2013 Anthracnose of grevillea
Pest Rating: B

Colletotrichum henanense F. Liu & L. Cai 2015
Pest Rating: B

Colletotrichum jiangxiense F. Liu & L. Cai 2015 Anthracnose
Pest Rating: B

Colletotrichum karstii Yan L. Yang, Zuo Y. Liu, K.D. Hyde & L. Cai 2011
Pest Rating: C

Colletotrichum karstii
Pest Rating: B

Colletotrichum Liriopes (Damm, P. F. Cannon & Crous, 2009)
Pest Rating: B

Colletotrichum orbiculare 
Pest Rating:  B 

Colletotrichum orchidophilum (Damm, P. F. Cannon & Crous 2012)
Pest Rating: B 

Colletotrichum petchii
Pest Rating: B

Colletotrichum phormii (Henn.) D.F. Farr & Rossman 2006
Pest Rating: C

Colletotrichum plurivorum Damm, Alizadeh & Toy. Sato 2018 
Pest Rating: B 

Colletotrichum queenslandicum
Pest Rating: B

Colletotrichum sansevieriae
Pest Rating: B

Colletotrichum siamense
Pest Rating: B

Colletotrichum spaethianum
Pest Rating: B

Colletotrichum theobromicola
Pest Rating: B

Colletotrichum Tropicale Rojas, Rehner & Samuels 2010
Pest Rating: B

Colletotrichum truncatum (Schwein.) Andrus & W.D. Moore 1935 Soybean anthracnose
Pest Rating: B

Coniella granati (Sacc.) Petr. & Syd. 1927 [1926]
Pest Rating: C

Corynespora cassiicola (Berk. & M. A. Curtis) C. T. Wei 1950
Pest Rating: B

Cronartium quercuum (Berk.) Miyabe ex Shirai 1899
Pest Rating: C 

Cytospora chrysosperma (Pers.: Fr.) Fr. 1818 Cytospora canker of poplar
Pest Rating: C

Dactylonectria torresensis (A. Cabral, Rego & Crous) L. Lombard & Crous 2014 Black foot
Pest Rating: C

Diaporthe columnaris (D. F. Farr & Castl.) Udayanga & Castl. 2016
Pest Rating: C

Diaporthe foeniculina (Sacc.) Udayanga & Castl. 2014
Pest Rating: B

Diaporthe helianthi Munt.-Cvetk., Mihaljc. & M. Petrov 1981
Pest Rating: B

Diaporthe pseudophoenicicola
Pest Rating: C

Diaporthe pseudomangiferae
Pest Rating: C 

Diaporthe rudis (Fr. : Fr.) Nitschke 1870
Pest Rating: C

Diaporthe vaccinii
Pest Rating: C

Didymella bryoniae
Pest Rating: B

Diplodia malorum Fuckel 1870
Pest Rating: B

Elsinoë australis Bitanc. & Jenkins 1936 Sweet orange scab 
Pest Rating: A

Erysiphe aquilegiae
Pest Rating: C

Erysiphe convolvuli de Candolle 1805 (Braun 1995)
Pest Rating: C

Erysiphe elevata (Burrill) U. Braun & S. Takam 2000
Pest Rating: C

Erysiphe peckii (U. Braun) U. Braun & S. Takam. 2000
Pest Rating: B

Erisyphe pisi (de Candolle 1805) ex St-Amans Powdery mildew of peas
Pest Rating: C

Exosporium petersii (Berk. & M. A. Curtis) U. Braun 2014
Pest Rating: B

Fusarium brachygibbosum
Pest Rating: C

Fusarium euwallaceae S. Freeman, Z. Mendel, T. Aoki & O’Donnell 2013
Pest Rating: B

Fusarium oxysporum f. sp. canariensis Mercier & Louvet 1973
Pest Rating: A

Fusarium oxysporum f. sp. palmarum Elliott & al. 2010 Fusarium wilt of palm
Pest Rating: B 

Ganoderma adspersum
Pest Rating: B

Ganoderma brownii (Murrill) Gilb. 1961
Pest Rating: C

Geosmithia pallida
Pest Rating: C

Greeneria uvicola
Pest Rating: B

Gymnosporangium globosum (Farl.) Farl. 1886
Pest Rating: A

Gymnosporangium yamadae Miyabe ex G. Yamada 1904
Pest Rating: A

Hemileia vastatrix Berk. & Broome (1869) Coffee leaf rust
Pest Rating: A

Ilyonectria capensis L. Lombard & Crous 2013
Pest Rating: C

Kweilingia divina
Pest Rating:  A

Leptosillia pistaciae (Voglmayr et al.) Voglmayr, comb. nov. 2019
Pest Rating:  B

Marasmiellus palmivorus
Pest Rating: C

Melampsoridium hiratsukanum: Alder Rust
Pest Rating: C

Monilinia fructicola (G. Winter) Honey 1928
Pest Rating: C

Neocercosporidium smilacis (Thüm.) U. Braun, C. Nakash., Videira & Crous 2017
Pest Rating: B 

Neofusicoccum mangiferae
Pest Rating: C

Neofusicoccum nonquaesitum Inderb, Trouillas, Bostock & Michailides 2010
Pest Rating: C

Penicillium chrysogenum Thom 1910 
Pest Rating: C

Peronosclerospora philippinensis
Pest Rating: C

Peronospora belbahrii
Pest Rating:  C  

Peronospora digitalidis
Pest Rating: C

Peronospora dipsaci Tul. 1854 ex de Bary 1863
Pest Rating: C

Peronospora mesembryanthemi 
Pest Rating:  B

Phacidiopycnis tuberivora (H.T. Güssow & W.R. Foster) B. Sutton 1980
Pest Rating: B

Phakopsora cherimoliae (Lagerh.) Cummins 1941 Annona rust
Pest Rating:  A

Phakopsora phyllanthi
Pest Rating:  C

Phyllosticta ampelicida (Engelmann) van der Aa 1861
Pest Rating: B 

Phyllosticta citricarpa (McAlpine) Van der Aa 1973 (teleomorph Guignardia citricarpa Kiely 1948) Citrus black spot
Pest Rating: A

Phyllosticta sphaeropsoidea Ellis & Everh. 1883 Leaf blotch of buckeyes and horse chestnuts
Pest Rating: C

Phyllosticta yuccae
Pest Rating: C

Phymatotrichopsis omnivora (Duggar) Hennebert 1973
Pest Rating: A

Phytophthora bisheria
Pest Rating:  B

Phytophthora Brassicae (De Cock & Man in ‘t Veld, 2002)
Pest Rating: B

Phytophthora cactorum
Pest Rating: B

Phytophthora cambivora
Pest Rating: B

Phytophthora hedraiandra
Pest Rating:  B

Phytophthora multivora P. M. Scott & T. Jung, 2009
Pest Rating:  C

Phytophthora niederhauserii 
Pest Rating:   B

Phytophthora occultans Man In’t Veld and Rosendahl (2015)
Pest Rating: B

Phytophthora parvispora
Pest Rating: B

Phytophthora pini Leonian 1925
Pest Rating: C

Phytophthora pseudocryptogea Safaief., Mostowf., G.E. Hardy & T.I. Burgess 2015 
Pest Rating: B

Phytophthora quercetorum Y. Balci & S. Balci 2008
Pest Rating: B

Phytophthora quercina
Pest Rating: B

Phytophthora ramorum Werres, De Cock & Man in ‘t Veld 2001
Pest Rating: A

Phytophthora siskiyouensis
Pest Rating:  B

Phytophthora tentaculata
Pest Rating:  B

Phytopythium vexans (de Bary) Abad, de Cock, Bala, Robideau, Lodhi & Lévesque 2014
Pest Rating:  C

Plasmopara constantinescui
Pest Rating:  B

Podosphaera caricae-papayae
Pest Rating:  B

Podosphaera xanthii
Pest Rating: C

Pseudocercospora myrticola
Pest Rating:  B

Pseudocercospora purpurea
Pest Rating: B

Pseudocercospora smilacicola
Pest Rating: B

Pseudocercospora theae (Cavara) Deighton 1987
Pest Rating: C

Pseudoidium hortensiae (Jørst.) U. Braun & R.T.A. Cook 2012 Hydrangea powdery mildew
Pest Rating: C

Puccinia crepidus-japonicae
Pest Rating: D 

Puccinia kuehnii 
Pest Rating: C  

Puccinia pelargonii-zonalis Doidge 1926 Rust of pelargonium
Pest Rating:  C 

Puccinia pentstemonis Peck 1885 Penstemon rust
Pest Rating:  C 

Puccinia psidii: Myrtle Rust
Pest Rating:  C 

Ramularia slaviicola
Pest Rating: C

Rhizopus stolonifer (Ehrenb.: Fr.) Vuill. 1902 Bulb rot
Pest Rating: C

Sarocladium oryzae
Pest Rating:  A

Sawadaea bicornis (Wallr.: Fr.) Miyabe 1937 Powdery mildew of maple
Pest Rating:  C

Sclerophthora rayssiae var. zeae
Pest Rating: C

Septocyta ruborum (Lib.) Petrak. 1967
Pest Rating: C

Septoria protearum
Pest Rating: B

Stemphylium solani 
Pest Rating: A

Talaromyces flavus (Klöcker) Stolk & Samson 1972
Pest Rating: D

Thekopsora minima
Pest Rating: C

Trametes versicolor (Linnaeus: Fries.)  Pilát 1920 [1921] turkey tails Pest Rating: C

Tranzschelia discolor` (Fuckel) Tranzschel & Litv., 1939 Synonym Tranzschelia pruni-spinosae var. discolor (Fuckel) Dunegan, 1938 Stone fruit rust  
Pest Rating: C

Tranzschelia mexicana
Pest Rating:  B

Tubakia californica Rooney-Latham & U. Braun 2018
Pest Rating:  C

Uromyces  asclepiadis Cooke 1877 milkweed rust
Pest Rating: A

Uromyces transversalis
Pest Rating: C

Ustilago esculenta Henn. 1895
Pest Rating: A

Ustilago maydis(DC.) Corda 1842 corn smut
Pest Rating: C

Venturia inaequalis (Cooke) G. Winter 1875 Apple Scab
Pest Rating: C

PHYTOPLASMAS: 

Candidatus Phytoplasma palmae (Lethal yellowing of palm phytoplasma)  
Pest Rating: A

Candidatus Phytoplasma pruni
(= Peach X-disease, Peach Rosette, Peach Red Suture, and Little Peach Phytoplasmas)
Pest Rating: C

Texas Phoenix Palm Decline Phytoplasma
Pest Rating:  A

VIRUSES and VIROIDS:

Alfalfa mosaic alfamovirus
Pest Rating: C

Alstroemeria necrotic streak virus
Pest Rating: A  

Apple mosaic virus
Pest Rating: C

Arabis mosaic nepovirus
Pest Rating: A

Bamboo Mosaic Virus (BaMV)
Pest Rating: B

Barley yellow dwarf luteovirus
Pest Rating: C

Bean common mosaic virus
Pest Rating: C

Brugmansia latent virus
Pest Rating: Q 

Cherry virus A
Pest Rating: D

Citrus Leaf Blotch Virus
Pest Rating: B 

Citrus tristeza virus
Pest Rating: A

Citrus viroid V
Pest Rating: B

Colombian Datura Virus
Pest Rating: C

Cucumber Green Mottle Mosaic Virus
Pest Rating: A

Cucumber mosaic virus
Pest Rating: C

Cucurbit chlorotic yellows virus
Pest Rating: B  

Cucurbit Yellow Stunting Disorder Virus
 Pest Rating:  B

Dracaena mottle virus
 Pest Rating:  C

Freesia Mosaic Virus
Pest Rating: B

Freesia Sneak Virus
Pest Rating:  B

Grapevine Pinot gris Virus (GPGV)
Rating: B

Grapevine Red Blotch Associated Virus
Pest Rating: B

Hibiscus Latent Fort Pierce Virus (HLFPV)
Pest Rating: B  

Hop Latent Viroid
Pest Rating: C

Impatiens necrotic spot virus
Pest Rating: C

Maize dwarf mosaic virus
Pest Rating: C 

Orchid fleck virus
Pest Rating: B

Papaya ringspot virus
Pest Rating: C

Pea Seed-borne Mosaic Virus (PSbMV)
Pest Rating:  B

Pepino Mosaic Virus (PepMV)
Pest Rating:  B

Plum bark necrosis stem pitting-associated virus
Pest Rating: C 

Potato leafroll virus
Pest Rating:  C

Potato Spindle Tuber Viroid
Pest Rating:  A 

Potato Virus X Potato interveinal mosaic
Pest Rating:  C

Rose Rosette Emaravirus
Pest Rating: C

Soil-borne wheat mosaic virus
Pest Rating: C 

Southern bean mosaic virus
Pest Rating: B

Soybean mosaic virus
Pest Rating: C

Squash Vein Yellowing Virus
Pest Rating:  B

Tobacco Etch Virus
Pest Rating:  C

Tobacco mosaic tobamovirus 
Pest Rating:  C

Tobacco ringspot nepovirus
Pest Rating:  A

Tomato Brown Rugose Fruit Virus
Pest Rating: A

Tomato Chlorotic Dwarf Viroid
Pest Rating:  A

Tomato Mottle Mosaic Virus
Pest Rating:  B

Tomato ringspot virus
Pest Rating:  C

Tomato spotted wilt tospovirus
Pest Rating:  C

Tomato Yellow Leaf Curl Virus
Pest Rating:  B

Wasabi Mottle Tobamovirus
Pest Rating:  C

Watermelon mosaic virus
Pest Rating:  C

Wheat streak mosaic virus
Pest Rating:  C

Zucchini yellow mosaic virus
Pest Rating: C