Disease Resistance Terminology

Monsanto Vegetable Seeds Division is transitioning to one approach for describing disease resistance and pathogen abbreviations in line with the current guidelines published by the International Seed Federation (ISF) system.

With regard to disease resistance descriptions, Monsanto Vegetable Seeds will use the term “High Resistance” (HR) and will no longer use the term “Resistance” (R). This is only a change in terminology and does not reflect a change in product performance.

Use of the “Intermediate Resistance” disease performance description remain unchanged.

Click here to view the updated Disease Resistance Abbreviations List.

HR = High Resistance. (The ability of a plant variety to highly restrict the activities of a specific pathogen or insect pest and/or to restrict the symptoms and signs of a disease, when compared to susceptible varieties. Highly Resistant varieties may exhibit some symptoms when specified pathogen or pest pressure is severe. New and/or atypical strains of the specific pathogen or pest may overcome the resistance, sometimes completely.)

IR = Intermediate Resistance. (The ability of a plant variety to restrict the growth and development of the specified pest or pathogen, but may exhibit a greater range of symptoms compared to highly resistant varieties. Intermediate resistant plant varieties will still show less severe symptoms or damage than susceptible plant varieties when grown under similar environmental conditions and/or pest or pathogen pressure.)

BEAN

Cl = Anthracnose (Colletotrichum lindemuthianum); Races: alpha, beta, gamma, delta, lambda, race 6, race 73
Ae = Aphanomyces root and hypocotyl rot (Aphanomyces euteiches)
Pss = Bacterial brown spot (Pseudomonas syringae pv. syringae)
BCMV = Bean common mosaic virus; Serotypes A and B
BCMNV = Bean common mosaic necrosis virus
BGMV = Bean golden mosaic virus
BYMV = Bean yellow mosaic virus
BCTV = Beet curly top virus “Beet curly top virus (formerly BCTV – Cal/Logan strain)”
BMCTV = Beet mild curly top virus “Beet mild curly top virus (formerly BCTV – Worland strain)”
BSCTV = Beet severe curly top virus “Beet severe curly top virus (formerly BCTV – CFH strain)”
Xap = Common bacterial blight (Xanthomonas campestris pv. phaseoli) Xanthomonas axonopodis pv. phaseoli
CMV = Cucumber mosaic virus
Fsp = Foot Rot (Fusarium solani f. sp. phaseoli)
Fop = Fusarium yellows (Fusarium oxysporum f. sp. phaseoli); Races 1 and 2
Psp = Halo blight (Pseudomonas syringae pv. phaseolicola); Races 1 and 2
Ua = Rust (Uromyces appendiculatus); Use race 38 for Ur10 and race 53 for Ur3; use races 40, 45, 49, 53, 59, 67, and 90 for complex combinations of resistance genes.
Ss = White mold (Sclerotinia sclerotiorum)

BROCCOLI

Xcc = Black rot (Xanthomonas campestris pv. campestris)
Pp = Downy mildew (Peronospora parasitica); California isolates, European isolates
Foc = Fusarium Yellows (Fusarium oxysporum f. sp. conglutinans)

CABBAGE

Xcc = Black rot (Xanthomonas campestris pv. campestris )
Px = Diamondback moth damage (Plutella xylostella)
Pp = Downy mildew (Peronospora parasitica)
Foc = Fusarium yellows (Fusarium oxysporum f. sp. conglutinans); Race 1
Mb = Ring spot (Mycosphaerella brassicicola)
Ss = Sclerotinia stem rot and watery soft rot (Sclerotinia sclerotiorum)
Tt = Thrips damage (Thrips tabaci)

CARROT

Ad = Alternaria leaf blight (Alternaria dauci)
Xhc = Bacterial leaf blight (Xanthomonas hortorum pv. carotae)
Ar = Black rot (Alternaria radicina)
Pv, Ps = Cavity spot (Pythium violae, Pythium sulcatum)
Cc = Cercospora leaf blight (Cercospora carotae)
Mh = Northern root-knot nematode (Meloidogyne hapla)
Eh = Powdery mildew (Erysiphe heraclei (Erysiphe polygoni))
Ma/Mi = Southern root-knot nematode (Meloidogyne incognita, Meloidogyne arenaria)

CAULIFLOWER

Pp = Downy mildew (Peronospora parasitica); California isolates, European isolates
Mb = Ring spot (Mycosphaerella brassicicola)
Ss = Sclerotinia stem rot and watery soft rot (Sclerotinia sclerotiorum)
Va/Vd = Va/Vd = Verticillium wilt (Verticillium albo-atrum /Verticillium dahliae)
Xcc = Black rot (Xanthomonas campestris pv. campestris )

CUCUMBER

Psl = Angular leaf spot (Pseudomonas syringae pv. lachrymans)
Co = Anthracnose (Colletotrichum orbiculare); Races 1, 2, and 3
Et = Bacterial wilt (Erwinia tracheiphila)
BPYV = Beet pseudo yellowing virus
CGMMV = Cucumber green mottle mosaic virus
CMV = Cucumber mosaic virus
CVYV = Cucumber vein yellowing virus; Serogroups I, II
CYSDV = Cucurbit yellow stunting disorder virus
Pcu = Downy mildew (Pseudoperonospora cubensis)
For = Fusarium crown and root rot (Fusarium oxysporum f. sp. radicis-cucumerinum)
Foc = Fusarium wilt (Fusarium oxysporum f. sp. cucumerinum)
Db = Gummy stem blight (Didymella bryoniae)
KGMMV = Kyuri green mottle mosaic virus
PRSV = Papaya ringspot virus; W strains
Ps = Phomopsis root rot “black root rot” (Phomopsis sclerotioides)
Gc = Powdery mildew (Golovinomyces cichoracearum (was Erysiphe cichoracearum))
Px = Powdery mildew (Podosphaera xanthii (was Sphaerotheca fuliginea))
Ccu = Scab (Cladosporium cucumerinum )
Cca = Target spot (Corynespora cassiicola)
WMV = Watermelon mosaic virus
ZYMV = Zucchini yellow mosaic virus; Many strains and variants

LETTUCE

MLBVV = Lettuce big-vein virus (Mirafiori lettuce big-vein virus)
BT = Bolting, Physiological
Ss = Corky root (Sphingomonas suberifaciens (Rhizomonas suberifaciens)); California isolate (CA-1), Florida isolate
Bl = Downy mildew (Bremia lactucae); "California pathotypes I, IIA, IIB, III, IV, V, VI, VII, novel 0, & 18, and emerging pathotypes European pathotypes BL 1-27"
Fol = Fusarium wilt (Fusarium oxysporum f. sp. lactucae)
GRSV = Groundnut ringspot virus
Xcv = Leaf spot (Xanthomonas campestris pv. vitians)
LMV = Lettuce mosaic virus
LNSV = Lettuce necrotic spot virus
Nr = Nasonovia (Nasonovia ribis-nigri); Controlled by known genes and Resistance breaking
Ec = Powdery mildew (Erysiphe cichoracearum)
Sm = Sclerotinia drop (Sclerotinia minor)
TB = Tipburn, Physiological
TBSV = Tomato bushy stunt virus
TCSV = Tomato chlorotic spot virus
TSWV = Tomato spotted wilt virus
Vd = Verticillium wilt (Verticillium dahliae)

MELON

Ac = Alternaria leaf blight (Alternaria cucumerina)
Co = Anthracnose (Colletotrichum orbiculare); Races 1 and 3
Ag = Aphids (Aphis gossypii (cotton melon aphid))
Aac = Bacterial fruit blotch (Acidovorax avenae subsp. citrulli)
CMV = Cucumber mosaic virus; Serogroup I, II
CVYV = Cucumber vein yellowing virus
CABYV = Cucurbit aphid-borne yellows virus
Pcu = Downy mildew (Pseudoperonospora cubensis)
Fom = Fusarium wilt (Fusarium oxysporum f. sp. melonis); Races: 0, 1, 1.2, and 2
Db = Gummy stem blight (Didymella bryoniae)
MNSV = Melon necrotic spot virus
PRSV = Papaya ringspot virus; W strains
Ps = Phomopsis root rot (Phomopsis sclerotioides)
Gc = Powdery mildew (Golovinomyces cichoracearum (was Erysiphe cichoracearum))
Px = Powdery mildew (Podosphaera xanthii (was Sphaerotheca fuliginea)); Races: 1, 2 (US), 2 (EU), 3 (France), 5 (EU)
S = Sulfur damage (Sulfur)
WMV = Watermelon mosaic virus
ZYMV = Zucchini yellow mosaic virus; Many strains and variants

ONION

Foc = Basal rot (Fusarium oxysporum f. sp. cepae)
Pd = Downy mildew (Peronospora destructor)
IYSV = Iris yellow spot virus
Pt = Pink root (Phoma terrestris )
Ap = Purple blotch (Alternaria porri)
Sv = Stemphylium leaf blight (Stemphylium vesicarium)
Cg = Twister (Colletotrichum gloeosporioides)

PEPPER

Ca,Cc, Cg = Anthracnose (Colletotrichum accutatum, Colletotrichum capsici, Colletotrichum gloeosporioides)
Xcv = Bacterial spot (Xanthomonas campestris pv. vesicatoria); Races 0 - 10
Rs = Bacterial wilt (Ralstonia solanacearum); Biovars 1, 3, 4; virulence varies
CaCV = Capsicum chlorosis virus
Cc = Cercospora leaf spot (Cercospora capsici)
ChiVMV = Chili veinal mottle virus (Chili veinal mottle potyvirus)
CMV = Cucumber mosaic virus
GBNV = Groundnut bud necrosis virus (Peanut bud necrosis virus) "Groundnut bud necrosis virus (Peanut bud necrosis virus)”
GRSV = Groundnut ringspot virus
PepMoV = Pepper mottle virus
PepYMV = Pepper yellow mosaic virus (formerly PVYm)
Pc = Phytophthora blight (Phytophthora capsici); Virulence varies
PVY = Potato virus Y virus; Strains: 0, 1, and 1.2
Lt = Powdery mildew (Leveillula taurica); Virulence varies
Mi/Ma/Mj = Southern root-knot nematode (Meloidogyne incognita, Meloidogyne arenaria, Meloidogyne javanica)
TEV = Tobacco etch virus
Tm = Tobamovirus virus (Tobamoviruses); Pathotypes: P0, P1, P1.2 and P1.2.3
TSWV = Tomato spotted wilt virus
Vd = Verticillium wilt (Verticillium dahliae)

SPINACH

Cd = Anthracnose (Colletotrichum dematium)
Cv = Cladosporium leaf spot (Cladosporium variable)
CMV = Cucumber mosaic virus
Pfs = Downy mildew (Peronospora farinose); Races: Pf 1 - 13
Fos = Fusarium wilt (Fusarium oxysporum f. sp. spinaciae)
Sb = Stemphylium leaf spot (Stemphylium botryosum)
Ao = White rust (Albugo occidentalis)

SQUASH

CGMMV = Cucumber green mottle mosaic virus
CMV = Cucumber mosaic virus; Serogroup I, II
Pcu = Downy mildew (Pseudoperonospora cubensis)
Fsc = Fusarium crown and root rot (Fusarium solani f. sp. cucurbitae)
Foc = Fusarium wilt (Fusarium oxysporum f. sp. cucumerinum)
Db = Gummy stem blight (Didymella bryoniae)
Mh = Northern root knot nematode (Meloidogyne hapla )
PRSV = Papaya ringspot virus; W strain
Ps = Phomopsis black root rot (Phomopsis sclerotioides)
Pc = Phytophthora root rot (Phytophthora capsici and other Phytophthora sp.)
Gc = Powdery mildew (Golovinomyces cichoracearum (was Erysiphe cichoracearum))
Px = Powdery mildew (Podosphaera xanthii (was Sphaerotheca fuliginea))
Rs = Rhizoctonia root rot (Rhizoctonia solani)
S = Silvering (The silverleaf whitefly – Bemisia argentifolii; Bemisia tobaci)
Mi = Southern root knot nematode (Meloidogyne incognita, Meloidogyne arenaria, Meloidogyne javanica)
SLCV = Squash leaf curl virus
WMV = Watermelon mosaic virus
ZYMV = Zucchini yellow mosaic virus; Many strains and variants

SWEET CORN

Cg = Anthracnose leaf blight and anthracnose stalk rot (Colletotrichum graminicola)
Ecc, Ecz = Bacterial stalk and top rot (Erwinia carotovora subsp. carotovora, Erwinia chrysanthemi pv. zeae)
Ps = Common rust (Puccinia sorghi)
Um = Common smut (Ustilago maydis); Many strains
Pp = Downy mildew (Peronosclerospora philippinensis)
Sr = Head smut (Sphacelotheca reiliana)
MDMV = Maize dwarf mosaic virus
Et = Northern corn leaf blight (Exserohilum turcicum)
Bm = Southern corn leaf blight and stalk rot (Bipolaris maydis)
Pp = Southern rust (Puccinia polysora)
Pst = Stewart’s disease (bacterial wilt) (Pantoea stewartii (Erwinia stewartii))
SCMV= Sugar cane mosaic virus; Strains: A

TOMATO

Aal = Alternaria stem canker (Alternaria alternata f. sp. lycopersici)
Cmm = Bacterial canker (Clavibacter michiganensis subsp. michiganensis )
Pst = Bacterial speck (Pseudomonas syringae pv. tomato); Pst race 0, 1
Xcv = Bacterial spot (Xanthomonas campestris pv. vesicatoria); Xcv tomato races 1, 2, 3, 4
Rs = Bacterial wilt (Ralstonia solanacearum); Biovars 1, 3, 4; Virulence varies
BCTV = Beet curly top virus
BMCTV = Beet mild curly top virus
BSCTV = Beet severe curly top virus
Pn = Buckeye fruit and root rot (Phytophthora nicotianae)
Pl = Corky root (Pyrenochaeta lycopersici)
CMV = Cucumber mosaic virus
As = Early blight (Alternaria solani)
For = Fusarium crown and root rot (Fusarium oxysporum f. sp. radicis-lycopersici )
Fol = Fusarium wilt (Fusarium oxysporum f. sp. lycopersici); US Races: 1, 2, and 3 (= European races 0, 1, and 2)
Ss = Gray leaf spot (Stemphylium solani)
Bc = Gray mold (Botrytis cinerea )
GBNV = Groundnut bud necrosis virus (Peanut bud necrosis virus)
GRSV = Groundnut ringspot virus
Pi = Late blight (Phytophthora infestans); Races 1 and 2
Ff = Leaf mold (Fulvia fulva); A, B, C, D, E
Mh = Northern root-knot nematode (Meloidogyne hapla)
PepMV = Pepino mosaic virus
PVY = Potato virus Y virus
Lt = Powdery mildew (Levillula taurica)
On = Powdery mildew (Oidium neolycopersicum (Oidium lycopersicum))
Mi/Ma/Mj = Southern root-knot nematode (Meloidogyne incognita, Meloidogyne arenaria, Meloidogyne javanica)
Cc = Target spot (Corynespora cassiicola)
TEV = Tobacco etch virus
ToCV = Tomato chlorosis virus
ToChV = Tomato chocolate virus
TICV = Tomato infectious chlorosis virus
ToMarV = Tomato marchitiez virus
ToMV = Tomato mosaic virus; Strains: 0, 1, 2, 1.2, and 2.2
ToMoV = Tomato mottle virus
TSWV = Tomato spotted wilt virus
ToTV = Tomato torrado virus
TYLCV = Tomato yellow leaf curl virus
TYLCSV = Tomato yellow leaf curl Sardinia virus
TYVSV = Tomato yellow vein streak virus (Tomato yellow vein streak begomovirus)
Va/Vd = Verticillium wilt (Verticillium albo-atrum / Verticillium dahliae); US races 1 and 2; Europe races 0 and 1

WATERMELON

Cl = Anthracnose (Colletotrichum lagenarium); Races: 1, 2, and 3
Aac = Bacterial fruit blotch (Acidovorax avenae subsp. citrulli)
CGMMV = Cucumber green mottle mosaic virus
CMV = Cucumber mosaic virus (Cucumber mosaic cucumovirus)
Fon = Fusarium wilt (Fusarium oxysporum f. sp. niveum); Races: 0, 1, 2
GBNV = Groundnut bud necrosis virus (Peanut bud necrosis virus)
Db = Gummy stem blight (Didymella bryoniae)
PRSV = Papaya ringspot virus; W strain
WMV = Watermelon mosaic virus
ZYMV = Zucchini yellow mosaic virus
Px = Powdery mildew (Podosphaera xanthii (was Sphaerotheca fuliginea))

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Disease Resistance Terminology