Virus and Viroid Plant Pathogens

Report
Virus and Viroid
Plant Pathogens
Kenneth L. Johnson II
USDA National Needs Fellow
University of Florida Plant Medicine Program
IPM Florida- IPM Apprentice
Kirk W. Martin SM(NRCM), CBSP
USDA National Needs Fellow
University of Florida Plant Medicine Program
IPM Florida-IPM Technical Information Specialist
Begomovirus-Bean golden
yellow mosaic virus
Family: Geminiviridae
Description:
Virions consist of a capsid. Virus
capsid is not enveloped. Capsid
is elongated and exhibits
icosahedral symmetry. The
capsid is geminate and has a
diameter of 18-20 nm. Capsids
appear hexagonal in outline.
The capsomer arrangement is
not obvious. The capsid consists
of 22 capsomers. With a length
of dimers 30 nm. (ICTV
database)
R.G. Milne, Istituto
di Virologia, CRN,
Torino, Italy
2
Begomovirus-Bean golden
yellow mosaic virus
Family: Geminiviridae
Host(s):
Wild bush bean,
Macroptilium lathyroides,
Common bush bean,
Phaseolus vulgaris,
Sieva bean, P. lunatus,
Threelobe false mallow,
Malvastrum
coromandelianum
Howard F. Schwartz,
Colorado State University,
Bugwood.org
Leaf symptoms:
vein yellow net,
interveinal chlorosis
Howard F. Schwartz,
Colorado State University,
Bugwood.org
3
Begomovirus-Bean golden
yellow mosaic virus
Family: Geminiviridae
Host(s):
Wild bush bean, Macroptilium
lathyroides,
Common bush bean, Phaseolus
vulgaris,
Sieva bean, P. lunatus,
Threelobe false mallow,
Malvastrum coromandelianum
Howard F. Schwartz,
Colorado State University,
Bugwood.org
Leaf symptoms:
vein yellow net,
interveinal chlorosis
Howard F. Schwartz,
Colorado State University,
Bugwood.org
Begomovirus-Bean golden
yellow mosaic virus
Family: Geminiviridae
UF IFAS Extension
Plant Disease Clinic
Diagnostic viral
inclusions:
Nuclear
Rounded dense
UF IFAS Extension
Plant Disease Clinic
bodies
Ring-shaped (rare)
Brittle crystals
UF IFAS Extension
Plant Disease Clinic
Closterovirus-Citrus tristeza
virus (CTV)
Family:
Closteroviridae
Description:
Virions consist of a capsid.
Virus capsid is not
enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
filamentous, flexuous with a
length of 2000 nm and a
width of 12 nm.
M. Bar-Joseph
Volcani Centre, Bet Dagan, Israel
Closterovirus-Citrus tristeza
virus (CTV)
Family: Closteroviridae
Host(s):
Citrus ssp. grafted onto Citrus
aurantium (sour orange) root stock
— quick decline, pitted stems.
C. paradisi (grapefruit) — stunt.
C. aurantifolia (lime) — die-back.
C. aurantifolia (Seville orange) —
seedling yellows.
C. reticulata (mandarin) — decline.
Aeglopsis chevalieri, Afraegle
paniculata (Nigerian powder-flaskfruit )), Pamburus missionis,
Passiflora gracilis (Annual
passionflower), Citropsis gilletiana,
Microcitrus australis
Disorders:
Tristeza
Stem-pitting
Seedling-yellows
Lime dieback
Diseases:
Quick decline
L. Navarro, Instituto
Valenciano de
Investigaciones
Agrarias, Bugwood.org
Closterovirus-Citrus tristeza
virus (CTV)
Family: Closteroviridae
Symptomology
Sweet orange-(Sweet orange stem
pitting strains)
Sour orange-(Seedling yellows)
severe stunting and yellowing
Grapefruit-(Seedling yellows)severe
stunting and yellowing , (Stempitting) stunted, the fruit is small
and misshapen, and yields are
considerably reduced; the wood of
the trunk and large limbs is pitted
with longitudinal depressions; in
some instances, the main scaffold
branches are twisted and distorted.
Lime-(Lime die-back strain) vein
flecking on young leaves, severe
pitting of wood of twigs and
branches, stunting of trees, and dieback with eventual death
Lemon-(Seedling yellows) severe
stunting and yellowing
Florida Division of Plant
Industry Archive, Florida
Department of Agriculture
and Consumer Services,
Bugwood.org
Closterovirus-Citrus tristeza
virus (CTV)
Melon aphid, Aphis gossypii
Lyle Buss, University of Florida
Brown citrus aphid, Toxoptera
citricida Lyle Buss, University of
Florida
Family: Closteroviridae
Vectors: Brown citrus aphid,
Toxoptera citricida and Melon
aphid, Aphis gossypii.
Diagnostic techniques:
Visual symptoms
Indexing on biological indicators
Management:
Disease-resistant cultivars
Disease-resistant rootstocks (will
not work on plants that virus
attacks directly i.e. certain lime,
grapefruit, pummelos, Pera sweet
orange and others (Reuther,
1978)
Possible cross-protection from
less mild strains of tristeza virus
L. Navarro, Instituto
Valenciano de Investigaciones
Agrarias, Bugwood.org
Tristeza virus affected fruit on right
Closterovirus-Citrus tristeza
virus (CTV)
Family: Closteroviridae
Diagnostic techniques:
Visual symptoms
Indexing on biological indicators
UF IFAS Extension
Plant Disease Clinic
CTV petiole inclusions
Diagnostic viral inclusions:
All cytoplasmic
Para-crystals
UF IFAS Extension
Plant Disease Clinic
Banded bodies
Densely stained phloem with
CTV stem inclusions
many vacuoles.
UF IFAS Extension
Plant Disease Clinic
CTV root inclusions
Cucumovirus-Cucumber
mosaic virus (CMV)
Family: Bromoviridae
Description:
Virions consist of a capsid.
Virus capsid is not
enveloped, round with
icosahedral symmetry. The
isometric capsid has a
diameter of 29-29.33-30
nm. Capsids appear round,
or hexagonal in outline.
The capsomer
arrangement is clearly
visible, or is not obvious.
The capsid consists of 32
capsomers. Virus
preparations contain more
than one particle
component.
Capsids all have the same
appearance. (ICTV
database).
R.G. Milne, Istituto di
Virologia, CRN,
Torino, Italy.
Cucumovirus-Cucumber
mosaic virus (CMV)
Family: Bromoviridae
Hosts:
Cucumber, Cucumis
sativus and many other
cucurbits — mosaics and
stunting, reduced fruit
yield.
Tomato, Lycopersicon
esculentum — mosaic,
reduction of leaf
laminae ("fernleaf") and
stunting.
Spinach, Spinacia
oleracea — severe
chlorosis and stunting.
David B. Langston,
University of Georgia,
Bugwood.org
CMV Infected cucumber
William M.
Brown Jr.,
Bugwood.org
CMV infected celery
Cucumovirus-Cucumber
mosaic virus (CMV)
Family: Bromoviridae
Vectors: Aphids
transmit in a nonpersistent manner
Cucumber infected by
Cucumber mosaic
virus
William M. Brown
Jr., Bugwood.org
William M. Brown
Jr., Bugwood.org
CMV infected cucumbers
Cucumovirus-Cucumber
mosaic virus (CMV)
Family: Bromoviridae
Diagnostic viral inclusions:
Cytoplasmic
Vacuolate
Dr. R. G. Christie, UF IFAS
Department of Plant Pathology
UF IFAS Extension
Plant Disease Clinic
Vesiculate
Crystalline cubes
Spheres
Hollow spheres
Dr. R. G. Christie, UF IFAS
Department of Plant Pathology
Begomovirus-Cucurbit leaf
crumple virus (CuLCrV)
Family: Geminiviridae
Description:
No official description
General Begomovirus
description:
Virions consist of a capsid.
Virus capsid is not
enveloped. Capsid is
elongated and exhibits
icosahedral symmetry. The
capsid is geminate, or
prolate in shape and has a
diameter of 15-20 nm.
Capsids appear round, or
hexagonal in outline. The
capsomer arrangement is
clearly visible, or is not
obvious. The capsid
consists of 22 capsomers.
With a length of 25-30 nm.
Zucchini squash infected with Cucurbit leaf crumple virus. Note
silverleaf symptoms in background due to feeding of immature
whiteflies. http://edis.ifas.ufl.edu/in716
Begomovirus-Cucurbit leaf
crumple virus (CuLCrV)
Family: Geminiviridae
Description:
Hosts:
Watermelon,
Citrullus lanatus
Cantaloupe and
Honeydew melon,
Cucumis melo
Squash and pumpkins,
Cucurbita palmate and
C. maxima, C. pepo
Florida Department
of Agriculture and
Consumer Services
Zucchini squash infected with Cucurbit leaf crumple virus. Note
silverleaf symptoms in background due to feeding of immature
whiteflies. http://edis.ifas.ufl.edu/in716
Begomovirus-Cucurbit leaf
crumple virus (CuLCrV)
Family: Geminiviridae
Cucurbits that were not
susceptible were acorn
squash, ananas
melon, butternut
squash, casaba melon,
Galia melon, golden
crenshaw melon, and
honeydew melon. Nonsusceptible crops
included cotton, pepper,
soybean, and
tomato.
Florida Department
of Agriculture and
Consumer Services
Cucurbit leaf crumple virus symptoms on
cucumber
Cucurbit leaf crumple virus symptoms on yellow
straight-necked squash
Begomovirus-Cucurbit leaf
crumple virus (CuLCrV)
Vector:
Silverleaf whitefly,
Bemisia argentifolii
Silverleaf whitefly, Bemisia argentifolii-vector of cucurbit leaf
crumple virus. Photo by Lyle Buss-University of Florida
Begomovirus-Cucurbit leaf
crumple virus (CuLCrV)
Diagnostic viral inclusions:
Nuclear
Bean golden mosaic
virus inclusions
(pictured) look very
similar to Cucurbit leaf
crumple virus
Rounded dense bodies
Ring-shaped (rare)
R. Cullen and M. Gooch,
UF IFAS Extension
Plant Disease Clinic
Brittle Crystals
Bean golden mosaic
virus inclusions
(pictured) close-up
R. Cullen and M. Gooch,
UF IFAS Extension
Plant Disease Clinic
Potexvirus-Cymbidium
mosaic virus (CymMV)
Family: Flexiviridae
Description:
Virions have a simple
construction (round or
elongated or spherical,
unenveloped virions); consist(s)
of a capsid (including inner and
outer capsid). Virus capsid is not
enveloped. Capsid/nucleocapsid
is elongated; exhibits helical
symmetry; capsid. Capsid shape
of elongated unenveloped
virion or tail of phage is
filamentous, is flexuous.
Elongated capsid, nucleocapsid
or phage tail is cross-striated.
Elongated capsids,
nucleocapsids or tails have only
or longest length(s) of 470 to
580 nm; is 13 nm wide. Axial
canal is distinct or indistinct, 3.4
to 12 with median 6.3 nm in
diameter. Basic helix is obvious
or obscure. Pitch of helix is 2.8
to 3.5 with median 3.331 nm.
Crude virus preparation
contains few virions or many
virions.
R. I. B. Francki
Department of Plant Pathology, Waite Agricultural
Research Institute, University of Adelaide, South
Australia
Cymbidium mosaic virus
Virus particles from purified preparation in uranyl acetate. Bar
represents 500 nm.
http://www.dpvweb.net/dpv/showdpv.php?dpvno=27
Potexvirus-Cymbidium
mosaic virus (CymMV)
Cymbidium
mosaic virus
symptoms
Family: Flexiviridae
Hosts:
•Cymbidium ssp. — mosaic,
necrosis.
•Cattleya ssp. — mosaic, flower
necrosis.
•Phalaenopsis ssp. — mosaic,
water soaked local lesions.
•Vanda ssp. — chlorotic flecks.
•Epidendrum ssp.,
•Laelia ssp.,
•Laeliocattleya ssp.,
•Oncidium ssp.,
•Zygopetalum ssp.,
•Vanilla fragrans
Florida Department of
Agriculture and
Consumer Services
Cymbidium mosaic
symptoms in
Cymbidium leaves.
http://ucce.ucdavis.edu/files/repositoryfiles/ca601p3-71680.pdf
Potexvirus-Cymbidium
mosaic virus (CymMV)
Family: Flexiviridae
Viral inclusions:
Widely distributed in host
tissues
Aggregates of virus particles
Long axis parallel
Banded bodies
Can be susceptible to
destruction
Dense bodies
Para-crystals
Florida Department
of Agriculture and
Consumer Services
Cymbidium mosaic virus-banded inclusions
Florida Department
of Agriculture and
Consumer Services
Cymbidium mosaic viral inclusions (see arrows)
Potyvirus-Dasheen mosaic
virus (DsMV)
Family: Potyviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
filamentous, flexuous
with a clear modal
length with a length of
750 nm (approximately).
Axial canal is indistinct.
Basic helix is obscure.
Zettler, Univ.
Florida 1970
Filamentous virus particles mounted in
phosphotungatate..
Potyvirus-Dasheen mosaic
virus (DsMV)
Family: Potyviridae
Hosts:
Aglaonema, Alocasia,
Amorphophallus, Arisaema,
Caladium, Cyrtosperma ssp. —
mosaic.
Cryptocoryne, Dieffenbachia,
Philodendron, Richardia,
Zantedeschia ssp. — mosaic
and leaf malformation.
Colocasia, Xanthosoma ssp. —
mosaic, chlorotic feathering.
Comments on host and host
range: there are conflicting
reports on the susceptibility of
non-aroids; in European studies
some are susceptible, but, in
tests Florida and Venezuela,
non-aroids were not infected
(Zettler and Hartman, 1986).
Photo by: F.W. Zettler
Chlorosis of Philodendron selloum leaf
N.J.Ko Florida
Department of
Agriculture and
Consumer Services
Dasheen mosaic virus in Taro
Potyvirus-Dasheen mosaic
virus (DsMV)
Family: Potyviridae
Hosts:
Aglaonema, Alocasia,
Amorphophallus, Arisaema,
Caladium, Cyrtosperma ssp. —
mosaic.
Cryptocoryne, Dieffenbachia,
Philodendron, Richardia,
Zantedeschia ssp. — mosaic
and leaf malformation.
Colocasia, Xanthosoma ssp. —
mosaic, chlorotic feathering.
Comments on host and host
range: there are conflicting
reports on the susceptibility of
non-aroids; in European studies
some are susceptible, but, in
tests Florida and Venezuela,
non-aroids were not infected
(Zettler and Hartman, 1986).
Photo by: F.W. Zettler
Mosaic and distortion of P. selloum leaf
N.J.Ko Florida
Department of
Agriculture and
Consumer Services
Dasheen mosaic virus in Dieffenbachia
Potyvirus-Dasheen mosaic
virus (DsMV)
Family: Potyviridae
Hosts:
Aglaonema, Alocasia,
Amorphophallus, Arisaema,
Caladium, Cyrtosperma ssp. —
mosaic.
Cryptocoryne, Dieffenbachia,
Philodendron, Richardia,
Zantedeschia ssp. — mosaic
and leaf malformation.
Colocasia, Xanthosoma ssp. —
mosaic, chlorotic feathering.
Comments on host and host
range: there are conflicting
reports on the susceptibility of
non-aroids; in European studies
some are susceptible, but, in
tests Florida and Venezuela,
non-aroids were not infected
(Zettler and Hartman, 1986).
ICTVdB - The Universal Virus
Database
Mosaic of taro (Colocasia esculenta) leaf
Potyvirus-Dasheen mosaic
virus (DsMV)
Family: Potyviridae
Diagnostic viral inclusions:
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and
scrolls in C-section
Laminated
aggregate
Amorphous cytoplasmic inclusions
Protein &
ribonucleoprotein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in
number &
aggregate with
some Potyvirus
infections
Florida Department
of Agriculture and
Consumer Services
I = Cylindrical Inclusions N=Nucleus
ICTVdB - The Universal Virus
Database
Electron micrograph of cylindrical inclusions in cell of
calla lily (Zantedeschia elliotiana). Bar represents 500
nm.
Hostuviroid-Hop stunt viroid
(Citrus viroid II) (HSVd)
Family: Pospiviroidae
Description:
Viroids are unencapsidated,
low molecular weight,
circular, single-stranded
infectious RNAs pathogenic
to plants. Sequences are the
primary basis for
comparison. The sequence
of the central conserved
region allows all
characterised viroids to be
classed into four groups.
Variation occurs within each
viroid "species" and an
arbitrary level of 90%
sequence similarity
currently separates variants
from species.
ICTVdB - The Universal Virus
Database
Photo of potato spindle tuber viroid which
closely resembles Hop stunt viroid (Citrus
viroid II)
Hostuviroid-Hop stunt viroid
(Citrus viroid II) (HSVd)
Family: Pospiviroidae
Hosts:
Hop stunt viroid
Hop stunt viroid - almond
Hop stunt viroid - apricot
Hop stunt viroid - citrus
Hop stunt viroid - cucumber
Hop stunt viroid - grapevine
Hop stunt viroid - peach
Hop stunt viroid - pear
Hop stunt viroid - plum
Citrus cachexia viroid
Cucumber pale fruit viroid
Peach dapple viroid
Plum dapple viroid
Green streaks observed under cracks induced by Hop stunt
viroid and Citrus viroid IV in trifoliate orange photo by C.
Vernière et al.
http://www.apsnet.org/publications/imageresources/Pages/
Nov_88-11-1.aspx
David Gent, USDA
Agricultural Research
Service, Bugwood.org
Common hops (Humulus lupulus L.)
A common hop plant showing symptoms of hop
stunt viroid infection in a field at Oregon, USA.
Tospovirus-Impatiens
necrotic spot virus (INSV)
Family: Bunyaviridae
Description:
Virions consist of an
envelope and a
nucleocapsid. Virus capsid
is enveloped. Virions are
spherical to pleomorphic.
Surface projections are
embedded in a lipid bilayer
that is 5 nm thick.
Capsid/nucleocapsid is
elongated with helical
symmetry. The
ribonucleocapsid is
filamentous and has a
width of 2-2.5 nm.
Nucleocapsids are circular.
Tospovirus-Impatiens
necrotic spot virus (INSV)
Family: Bunyaviridae
Hosts:
Impatiens spp.
most leaves symptomless,
some necrotic spots with
necrotic rings in young
leaves.
Other hosts:
Gloxinia
Gerbera daisy
Oncidium orchid
Chrysanthemum
Tomato
Coleus
Wild geranium
Department of Plant Pathology Archive,
North Carolina State University, Bugwood.org
Impatiens necrotic spot virus symptoms on
chrysanthemum
Department of Plant Pathology Archive,
North Carolina State University, Bugwood.org
Impatients necrotic spot virus symptoms on
coleus
Tospovirus-Impatiens
necrotic spot virus (INSV)
Family: Bunyaviridae
Hosts:
Impatiens spp.
most leaves symptomless,
some necrotic spots with
necrotic rings in young
leaves.
Other hosts:
Gloxinia
Gerbera daisy
Oncidium orchid
Chrysanthemum
Tomato
Coleus
Wild geranium
Department of Plant Pathology Archive,
North Carolina State University, Bugwood.org
Impatiens necrotic spot virus symptoms on
gloxinia
Mary Ann Hansen, Virginia Polytechnic Institute
and State University, Bugwood.org
Impatients necrotic spot virus symptoms on
tomato fruit
Tospovirus-Impatiens
necrotic spot virus (INSV)
Family: Bunyaviridae
Vector:
Western flower thrips,
Frankliniella
occidentalis
Lyle Buss
University of
Florida
Tospovirus-Impatiens
necrotic spot virus (INSV)
Family: Bunyaviridae
Diagnostic viral
inclusions:
Vacuolate
Dense, irregular with
projections
Crystalline
All photographs by
Florida Department
of Agriculture and
Consumer Services
Tobamovirus-Odontoglossum
ringspot virus (ORSV)
Family: Unassigned
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
rod-shaped, straight
with a clear modal
length with a length of
mostly 300 nm (but also
shorter, broken virions,
width of 18 nm. Axial
canal is distinct.
ICTVdB - The Universal Virus
Database
Tobamovirus-Odontoglossum
ringspot virus (ORSV)
Family: Unassigned
Hosts:
Vector:
Virus is not
transmitted by a
vector. Virus is
transmitted by
mechanical
inoculation.
Juliana Frettas-Astua
Florida Department
of Agriculture and
Consumer Services
Juliana Frettas-Astua
Florida Department
of Agriculture and
Consumer Services
Tobamovirus-Odontoglossum
ringspot virus (ORSV)
Family: Unassigned
Diagnostic viral
inclusions:
All cytoplasmic
Hexagonal plates
Virus particles
Stacked plates
Virus particles
Paracrystals
Virus particles
- old infection
X - Bodies
Vacuolate
Photograph bu
Nan-Jing Ko
Tobamovirus inclusions stain in Azure A
stain with heat only. Photograph by NanJing Ko
Photograph bu
Nan-Jing Ko
Inclusions stained with Orange
Green
Potyvirus-Papaya ringspot
virus (PRSV)
Family: Potyviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid
is filamentous,
flexuous with a clear
modal length with a
length of 760-800 nm
and a width of 12 nm.
Alberto Pantoja, USDA
Agricultural Research Service,
Bugwood.org
Potyvirus-Papaya ringspot
virus (PRSV)
Family: Potyviridae
Hosts:
Vector:
Virus is transmitted by
aphids. Virus is also
transmitted by
mechanical
inoculation; not
transmitted by seeds.
Alberto Pantoja, USDA
Agricultural Research Service,
Bugwood.org
Potyvirus-Papaya ringspot
virus (PRSV)
Family: Potyviridae
Diagnostic viral inclusions:
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and scrolls
in C-section
Laminated aggregate
Amorphous cytoplasmic inclusions
Protein & ribonucleoprotein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number &
aggregate with some
Potyvirus infections
UF IFAS Extension Plant Disease Clinic
Pospiviroid-Potato spindle
tuber viroid (PSTVd)
Family: Pospiviroidae
Hosts:
Nucleic acid is nonencapsidated, circular,
single-stranded RNA
ICTVdB - The Universal Virus
Database
Potato spindle tuber viroid
Pospiviroid-Potato spindle
tuber viroid (PSTVd)
Family: Pospiviroidae
Hosts:
Potato, Solanum
tuberosum
Tomato, Solanum
esculentum
R.P. Singh, Bugwood.org
Potato cv ‘Kennebec’, Solanum tuberosum,
center plant infected with Potato spindle tuber
viroid, outer two plants are healthy
Central Science Laboratory,
Harpenden Archive, British Crown, Bugwood.org
Tomato, Solanum esculentum infected by
Potato spindle tuber viroid
Pospiviroid-Potato spindle
tuber viroid (PSTVd)
Family: Pospiviroidae
Hosts:
Potato, Solanum
tuberosum
Tomato, Solanum
esculentum
Plant Protection Service Archive,
Plant Protection Service, Bugwood.org
Potatoes infected with potato spindle tuber
viroid. Healthy potato on left others diseased
USDA Agricultural Research
Service Archive,
USDA ARS, Bugwood.org
First and third rows of potatoes from top are
healthy; second and fourth rows are infected
with the potato spindle tuber viroid
Potyvirus-Potato virus Y
(PVY)
Family: Potyviridae
Description:
Virions consist of a capsid.
Virus capsid is not
enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
filamentous, flexuous with a
clear modal length with a
length of 684 nm (from
purified preparations
(Delgado-Sanchez and
Grogan, 1966)), or 730 nm
and a width of 11 nm. Axial
canal is indistinct; 2-3 nm in
diameter. Basic helix is
obscure. Pitch of helix is 3.3
nm (Varma et al., 1968).
Rothamsted Research.
Potato virus Y
Potyvirus-Potato virus Y
(PVY)
Family: Potyviridae
Hosts:
Potato, Solanum
tuberosum
Tobacco, Nicotiana
tabacum
Pepper, Capsicum
annuum
Vector: transmitted by
aphids, mechanical
means or transmission
by grafting.
Bruce Watt, University of Maine,
Bugwood.org
Rugose leaf symptoms on potato infected
with potato virus Y
Bruce Watt, University of Maine,
Bugwood.org
Potato infected with potato virus Y
Potyvirus-Potato virus Y
(PVY)
Cylindrical
Amorphous
Family: Potyviridae
Diagnostic viral inclusions:
Microcrystals
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and scrolls
in C-section
Laminated aggregate
Amorphous cytoplasmic inclusions
Protein & ribonucleoprotein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number &
aggregate with some
Potyvirus infections
UF IFAS Extension Plant Disease Clinic
UF IFAS Extension Plant Disease Clinic
Stomata guard cells filled with inclusions of PVY
Ipomovirus-Squash vein
yellowing virus (SqVYV)
Family: Potyviridae
Description:
The virus, for which the name Squash
vein yellowing virus (SqVYV) is
proposed, has flexuous rod-shaped
particles of ~840 nm in length.
Ipomovirus-Squash vein
yellowing virus (SqVYV)
Family: Potyviridae
Squash Vein Yellowing Virus, Causal
Agent of Watermelon Vine
Decline in Florida
Hosts:
The host range of SqVYV
appears to be limited to
cucurbits including two weedy
varieties of
cucurbits found in Florida,
Momordica charantia L.
(Balsam-apple) and Melothria
pendula L. (creeping
cucumber) (Adkins et al. 2008).
These weeds may be important
reservoirs for SqVYV and help it
to
survive between crops.
Scott Adkins, 2008 .
Plant Disease
Early symptoms of WVD. Photography credit: Scott Adkins
http://www.freshfromflorida.com/pi/enpp/pathology/pathcirc/pp407.pdf
Vectors:
Whitefly, Bemesia tabaci
Scott Adkins,,
FDACS DPI
Symptoms several weeks later. Photography credit: Scott Adkins
http://www.freshfromflorida.com/pi/enpp/pathology/pathcirc/pp407.pdf
Ipomovirus-Squash vein
yellowing virus (SqVYV)
Family: Potyviridae
Hosts:
The host range of SqVYV
appears to be limited to
cucurbits including two
weedy varieties of
cucurbits found in Florida,
Momordica charantia L.
(Balsam-apple) and
Melothria pendula L.
(creeping
cucumber) (Adkins et al.
2008). These weeds may be
important reservoirs for
SqVYV and help it to
survive between crops.
Vectors:
Whitefly, Bemesia tabaci
Scott Adkins, 2008 .
Plant Disease
Melothria pendula a cucurbit weed that
can potentially serve as a viral reservoir
Scott Adkins,,
FDACS DPI
Watermelon rind damaged by the Squash vein
yellowing virus causing WVD symptoms. Photography
credit: Scott Adkins
http://www.freshfromflorida.com/pi/enpp/pathology/
pathcirc/pp407.pdf
Ipomovirus-Squash vein
yellowing virus (SqVYV)
Family: Potyviridae
Diagnostic viral inclusions:
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and scrolls
in C-section
Laminated aggregate
Amorphous cytoplasmic inclusions
Protein & ribonucleoprotein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number &
aggregate with some
Potyvirus infections
Florida Department of Agriculture
and Consumer Svcs., Department of
Plant Industry
CI=Cylindrical inclusions; N=Nucleus
Squash vein yellowing virus
http://www.freshfromflorida.com/pi/enpp/pathology/fl
orida_viruses/Cucurbits/SqVYV/SqVYVpage.htm
Potyvirus-Sugarcane mosaic
virus (SCMV)
Family: Potyviridae
Description:
Morphology
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
filamentous, flexuous
with a clear modal
length with a length of
730-755 nm and a width
of 13 nm. Axial canal is
indistinct. Basic helix is
obscure.
Filamentous particles
of sugarcane mosaic
virus strain H
mounted in
phosphotungstate.
Bar represents 200
nm.
http://www.dpvweb.net/dpv/showfi
g.php?dpvno=88&figno=05
Potyvirus-Sugarcane mosaic
virus (SCMV)
Family: Potyviridae
Hosts:
Saccharum sp. —
systemic mosaic.
Sorghum bicolor —
necrotic local lesion,
then systemic mosaic,
necrosis.
S. halepense — systemic
mosaic.
Zea mays — systemic
mosaic, ringspots.
Most dicotyledonous
plants.
Photograph 1 Sugarcane variety C.P.31-294
systemically infected by sugarcane mosaic virus
strain B. (Courtesy A. G. Gillaspie.)
http://www.dpvweb.net/dpv/showfig.php?dpvno=88&figno=01
Photograph 2 Sugarcane variety C.P.31-294
systemically infected by sugarcane mosaic virus
strain D. (Courtesy A. G. Gillaspie.)
http://www.dpvweb.net/dpv/showfig.php?dpvno=88&figno=02
Photograph 6 Systemic necrosis produced by
sugarcane mosaic virus strain A in sorghum.
http://www.dpvweb.net/dpv/showfig.php?dpvno=88&figno=06
Photograph 7 Local necrotic lesions produced in Atlas
sorghum by sugarcane mosaic virus strain E.
(Courtesy J. L. Dean.)
http://www.dpvweb.net/dpv/showfig.php?dpvno=88&figno=07
Potyvirus-Sugarcane mosaic
virus (SCMV)
Family: Potyviridae
Vector:
Virus is transmitted nonpersitently by the aphids:
Dactynotus ambrosiae,
Rusty plum aphid,
Hysteroneura setariae,
Corn leaf aphid,
Rhopalosiphum maidis,
Toxoptera graminum.
Transmission:
Virus is transmitted by
mechanical inoculation;
transmitted by grafting;
transmitted by seeds; not
transmitted by pollen.
Merle Shepard, Gerald R.Carner, and
P.A.C Ooi, Insects and their Natural
Enemies Associated with Vegetables
and Soybean in Southeast Asia,
Bugwood.org
Corn leaf aphid , Rhopalosiphum maidis
Potyvirus-Sugarcane mosaic
virus (SCMV)
Family: Potyviridae
Diagnostic viral inclusions:
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and scrolls
in C-section
Laminated aggregate
Amorphous cytoplasmic inclusions
Protein & ribonucleoprotein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number &
aggregate with some
Potyvirus infections
Cylindrical inclusions of sugar cane mosaic in
Zea mays (corn). The inclusion at the far right is
next to a nucleus.
Potyvirus-Tobacco etch virus
(TEV)
Family: Potyviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
filamentous, flexuous
with a clear modal
length with a length of
730-750 nm and a width
of 12-13 nm. Basic helix
is obvious (in UF).
Potyvirus photograph from IACR Rothamsted
Potyvirus-Tobacco etch virus
(TEV)
Family: Potyviridae
Hosts:
Cassia obtusifolia — leaf
mottling, malformation and
necrosis, stunting and reduced
seed yield.
Capsicum annuum — mottling,
mosaic and leaf malformation,
fruit malformation, stunting.
Datura stramonium — leaf
mottling, vein banding and
malformation, suppression of
fruit spines.
Lycopersicon esculentum — leaf
mottling and distortion, severe
yield reductions.
Nicotiana tabacum — mottling
and necrotic leaf etching.
Physalis ssp. — leaf chlorosis.
Florida Division of Plant Industry Archive, Florida Department of
Agriculture and Consumer Services, Bugwood.org
Florida Division of Plant Industry Archive, Florida
Department of Agriculture and Consumer Services,
Bugwood.org
Potyvirus-Tobacco etch virus
(TEV)
Family: Potyviridae
Hosts:
Cassia obtusifolia — leaf
mottling, malformation and
necrosis, stunting and reduced
seed yield.
Capsicum annuum — mottling,
mosaic and leaf malformation,
fruit malformation, stunting.
Datura stramonium — leaf
mottling, vein banding and
malformation, suppression of
fruit spines.
Lycopersicon esculentum — leaf
mottling and distortion, severe
yield reductions.
Nicotiana tabacum — mottling
and necrotic leaf etching.
Physalis ssp. — leaf chlorosis.
Clemson University - USDA Cooperative
Extension Slide Series, Bugwood.org
Tobacco etch virus symptoms on tobacco
Potyvirus-Tobacco etch virus
(TEV)
Family: Potyviridae
Vector: Aphids
especially
Green peach aphid,
Myzus persicae
Lyle Buss
University of
Florida
Winged green peach aphid Myzus persicae
Lyle Buss
University of
Florida
Adult female green peach aphid Myzus persicae
Potyvirus-Tobacco etch virus
(TEV)
Family: Potyviridae
Diagnostic viral inclusions:
Microcrystals
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and scrolls
in C-section
Laminated aggregate
Amorphous cytoplasmic inclusions
Protein & ribonucleoprotein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number &
aggregate with some
Potyvirus infections
Pinwheel
Inclusions
Nucleus
UF IFAS Extension Plant Disease Clinic
Inclusion
Tobamovirus-Tobacco mosaic
virus (TMV)
Family: No family
assigned
Description:
Virions consist of a capsid.
Virus capsid is not
enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
rod-shaped, straight with a
clear modal length with a
length of 300 nm and a
width of 18 nm. Axial canal
is distinct; 2 nm in
diameter. Basic helix is
obvious. Pitch of helix is
2.3 nm.
Dr. Robley Williams
Tobamovirus-Tobacco mosaic
virus (TMV)
Family: No family assigned
Host:
Nicotiana tabacum — leaf
mosaic, severe crop losses.
Also found in many other plant
species.
Vector/Transmission:
Virus is not transmitted by a
vector. Virus is transmitted by
mechanical inoculation;
transmitted by grafting;
transmitted by contact between
hosts; transmitted by seeds
(occasionally transmitted through
the testa, but not through the
embryo, not transmitted by
pollen.
Transmitted by dodder, Cuscuta
campestris, C. japonica and C.
subinclusa
Milton Zaitlin
Symptoms of TMV in Nicotiana tabacum cv Turkish
Samsun. Photographed three weeks post-inoculation.
Milton Zaitlin
Local necrotic lesions produced upon TMV infection in
Nicotiana tabacum of the NN genotype. Photographed
one week post-inoculation.
Tobamovirus-Tobacco mosaic
virus (TMV)
Family: No family
assigned
Diagnostic viral
inclusions:
All cytoplasmic
Hexagonal plates
Virus
particles
Stacked plates
Virus
particles
Paracrystals
Virus
particles – old
infection
X - Bodies
Vacuolate
Dr. R. G. Christie, UF IFAS
Department of Plant Pathology
Tobamovirus-Tobacco mosaic
virus (TMV)
Family: No family
assigned
Diagnostic viral
inclusions:
All cytoplasmic
Hexagonal plates
Virus
particles
Stacked plates
Virus
particles
Paracrystals
Virus
particles – old
infection
X - Bodies
Vacuolate
UF IFAS Extension Plant Disease Clinic
Dr. R. G. Christie, UF IFAS
Department of Plant Pathology
Tobravirus-Tobacco rattle
virus (TRV)
Family: No family
assigned
Description:
Virions consist of a capsid.
Virus capsid is not
enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
rod-shaped, straight with a
clear modal length with a
length of 46-114 nm (T), or
180-197 nm (B, width of 22
nm. Axial canal is distinct;
4 nm in diameter. Basic
helix is obvious. Pitch of
helix is 2.5 nm.
IACR Rothamsted
Tobravirus-Tobacco rattle
virus (TRV)
Family: No family assigned
Hosts:
Stellaria media, Viola arvensis
— few symptoms, mottling.
Beta vulgaris, Spinacia oleracea
— chlorotic or necrotic local
lesions; systemic mottle.
Capsicum annuum — ringspots
or line patterns.
Solanum tuberosum — necrotic
local lesions; systemic chlorotic
or necrotic spots and streaks.
Nicotiana tabacum — necrotic
local lesions, necrotic or
chlorotic ringspots; systemic
necrosis, ringspots or line
patterns, mottling.
Narcissus pseudonarcissus,
Tulipa sp., Hyacinthus sp. —
mottling.
G. Chastagner1 and H. R.
Pappu, Washington State
Univ.
Symptoms of Tobacco rattle virus on peony
Ben Lockhart, University
of Minnesota Extension
Tobacco Rattle virus on hosta 'ananuma'
Tobravirus-Tobacco rattle
virus (TRV)
Family: No family assigned
Transmission/ Vectors:
Virus is transmitted by a vector.
Virus is transmitted by
mechanical inoculation;
transmitted by grafting; not
transmitted by contact between
hosts; transmitted by seeds (up
to 40% in Viola arvensis or only
to 1% in Capsella bursapastoris).
Vector Transmission:
Virus is transmitted by
nematodes; family
Trichodoridae; Paratrichodorus
allius, P. anemones, P. christiei,
P. nanus, P. pachydermus, P.
teres, Trichodorus minor, T.
primitivus, T. viruliferus.
Anterior of Paratrichodorus minor a vector
of Tobacco rattle virus
http://plpnemweb.ucdavis.edu/nemaplex
/Taxadata/G097S1.HTM
Tobravirus-Tobacco rattle
virus (TRV)
Family: No family
assigned
Diagnostic viral
inclusions:
Inclusions of Tobacco rattle virus in subveinal
epidermal cells of an inoculated leaf (Nicotiana
tabaccum) stained with Azure A.
(Pictures taken from "Light and Electron Microscopy of
Plant Virus Inclusions" by R. G. Christie and J. R.
Edwardson)
Nepovirus-Tobacco ringspot
virus (TRSV)
Family: Comoviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped, round
with icosahedral
symmetry. The isometric
capsid has a diameter of
25-29 nm (virions may
swell at pH 8.0). Capsids
appear hexagonal in
outline. The capsomer
arrangement is not
obvious.
Nepovirus-Tobacco ringspot
virus (TRSV)
Family: Comoviridae
Hosts:
Cucumis sativus,
Glycine max,
Lycopersicon
esculentum, Nicotiana
tabacum — necrotic
spots, mottling,
chlorotic ringspots and
vein banding.
Virginia Tech Learning Resources
Center, Virginia Polytechnic Institute
and State University, Bugwood.org
Tobacco ringspot virus symptoms on tobacco
Virginia Tech Learning Resources Center, Virginia
Florida Division of Plant Industry
Archive, Florida Department of
Agriculture and Consumer Services,
Bugwood.org
Tobacco ringspot virus symptoms on bean
Nepovirus-Tobacco ringspot
virus (TRSV)
Family: Comoviridae
Vector:
Trichodorus ssp., a nematode vector of Tobacco ringspot virus.
http://plpnemweb.ucdavis.edu/Nemaplex/images/Trichodorus6.JPG
Anterior view of Trichodorus ssp. nematode
http://plpnemweb.ucdavis.edu/Nemaplex/images/TrichodorusAnt.JPG
Nepovirus-Tobacco ringspot
virus (TRSV)
Family: Comoviridae
Diagnostic viral
inclusions:
Vacuolate - Vesiculate
Virus crystals & aggregates
Xylem blockage
Uneven distribution
Glandular hair cells
Guard cells
Phloem
Sub-veinal
UF IFAS Extension Plant Disease Clinic
Irregular vacuolate
Irregular non-vacuolate
Crystalloid
Microcrystal
UF IFAS Extension Plant Disease Clinic
Nicotiana benthamiana 1000X
Crinivirus-Tomato infectious
chlorosis virus (TICV)
Family:
Closteroviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid
is filamentous,
flexuous with a length
of 850-900 nm and a
width of 12 nm.
Crinivirus-Tomato infectious
chlorosis virus (TICV)
Family: Closteroviridae
Hosts:
Lycopersicon esculentum —
interveinal yellowing,
necrosis and severe yield
loss.
tomato, (Lycopersicon
esculentum), tomatillo
(Physalis ixocarpa), potato
(Solanum tuberosum),
artichoke (Cynara scolymus),
lettuce (Lactuca sativa) and
petunia (Petunia hybrida).
Vector:
Trialeurodes vaporariorum
transmission by Bemisia spp.
Is uncertain
W. M. Wintermantel,
USDA-ARS, Salinas,
CA, USA.
W. M. Wintermantel,
USDA-ARS, Salinas,
CA, USA.
Tomato plant infected with
Tomato infectious chlorosis
virus showing interveinal
chlorosis and mild necrosis
on leaflet
Tomato plant infected with
Tomato infectious chlorosis
virus showing interveinal
chlorosis and mild necrosis
on leaflet
http://www.agf.gov.bc.ca/cropprot/emergingvir
uses.htm
http://www.agf.gov.bc.ca/cropprot/emergingvir
uses.htm
Crinivirus-Tomato infectious
chlorosis virus (TICV)
Family:
Closteroviridae
Diagnostic viral
inclusions:
All cytoplasmic
Paracrystals
Banded bodies
Densely stained phloem
with many vacuoles.
Tospovirus-Tomato spotted
wilt virus (TSWV)
Family: Bunyaviridae
Description:
Virions consist of an envelope
and a nucleocapsid. Virus
capsid is enveloped. Virions
are spherical to pleomorphic
measuring 80-100 nm in
diameter. The envelope
surrounds three
nucleocapsids. Surface
projections are distinctive
spikes that are surrounded by
a prominent fringe. Surface
projections are embedded in
a lipid bilayer that is 5 nm
thick. Surface projections are
5-10 nm long.
Capsid/nucleocapsid is
elongated and exhibits helical
symmetry. The
ribonucleocapsid is
filamentous with a length of
200-3000 nm (depending on
arrangement) and a width of
2-2.5 nm. Nucleocapsids are
circular.
IACR Rothamsted
Tomato spotted wilt virus
Tospovirus-Tomato spotted
wilt virus (TSWV)
Family: Bunyaviridae
Hosts:
Ananas comosus, Bidens
pilosa, Capsicum annuum,
Datura stramonium,
Helianthus annuus, Ipomoea
congesta, Lactuca sativa,
Malva parviflora, Nicandra
physalodes, Phaseolus
vulgaris, Physalis peruviana,
Zinnia elegans, Arachis
hypogaea, Canavalia gladiata,
C. obtusifolia, C. occidentalis,
Crotalaria juncea, Desmodium
triflorum, Glycine max, Pisum
sativum, Tephrosia purpurea,
Vicia faba, Vigna mungo, V.
radiata, V. unguiculata,
Lycopersicon esculentum,
Nicotiana tabacum, Solanum
melongena, S. capsicastrum,
S. tuberosum and many other
species
Jeffrey W. Lotz, Florida Department
of Agriculture and Consumer
Services, Bugwood.org
Florida Division of Plant Industry Archive,
Florida Department of Agriculture and
Consumer Services, Bugwood.org
Tospovirus-Tomato spotted
wilt virus (TSWV)
Family: Bunyaviridae
Symptoms:
necrotic and chlorotic
local lesions, systemic
wilting, necrosis,
spotting, streaking,
mosaic, mottling, leaf
shape malformation,
vein yellowing,
ringspots, line
patterns, yellow
netting and flower
colour-breaking.
David B. Langston, University
of Georgia, Bugwood.org
Tomato spotted wilt symptoms on pepper
leaves
David B. Langston, University
of Georgia, Bugwood.org
Tomato spotted wilt symptoms on pepper
Tospovirus-Tomato spotted
wilt virus (TSWV)
Family: Bunyaviridae
Vector:
Nine species are reported as
vectors: Frankliniella
occidentalis (western flower
thrips); F schultzei, F fusca
(tobacco thrips); Thrips
tabaci (onion thrips); T
setosus, T moultoni; F
tenuicornis, Lithothrips
dorsalis, and Scirtothrips
dorsalis. The first four are
considered the most
important vectors because
of their wide distribution
and the overlapping host
ranges of these species and
TSWV.
J.P. Sanderson, Cornell University,
Ithaca, NY
Western flower thrips larvae, Frankliniella
occidentalis
Lyle Buss, University of
Florida
Tobacco thrips, Frankliniella fusca
Tospovirus-Tomato spotted
wilt virus (TSWV)
Family: Bunyaviridae
Diagnostic viral
inclusions:
UF IFAS Extension Plant Disease Clinic
Vacuolate
Tomato spotted wilt virus inclusions
Dense, Irregular with
projections
Crystalline
UF IFAS Extension Plant Disease Clinic
Begomovirus-Tomato yellow
leaf curl virus (TSWV)
Family: Geminiviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped. Capsid
is elongated and
exhibits icosahedral
symmetry. The capsid
is geminate and has a
diameter of 20 nm.
Capsids appear
hexagonal in outline.
The capsomer
arrangement is not
obvious. With a length
of dimers 30 nm.
Begomovirus-Tomato yellow
leaf curl virus (TSWV)
Family: Geminiviridae
Hosts:
• In tomato, symptoms are
more severe when infected
at an earlier age and vary
somewhat among the
different cultivars.
• In tomato, upward curling
of leaves; mottling and
often chlorotic leaf margins.
• In tomato, leaves are
reduced in size.
• In tomato, plants are
stunted.
• Flower abscission in
tomato resulting in greatly
reduced fruit set.
• No symptoms are
observed in pepper.
Don Ferrin, Louisiana State Univ. Agric. Ctr. Bugwood.org
Florida Department of Agriculture
and Consumer Svcs, Bugwood.org
Begomovirus-Tomato yellow
leaf curl virus (TSWV)
Family: Geminiviridae
Vector: Virus is
transmitted by
immature and adult
white flies, Bemesia
tabaci. Virus is
transmitted by
mechanical
inoculation (poorly,
transmitted by
grafting; not
transmitted by contact
between hosts).
Don Ferrin, Louisiana State Univ. Agric. Ctr. Bugwood.org
Begomovirus-Tomato yellow
leaf curl virus (TSWV)
Family: Geminiviridae
Diagnostic viral
inclusion:
Nuclear
Rounded dense bodies
Florida Department of Agriculture
and Consumer Svcs, Bugwood.org
Ring-shaped (rare)
Brittle crystals
UF IFAS Extension Plant Disease Clinic
UF IFAS Extension Plant Disease Clinic
Potyvirus-Watermelon
mosaic virus (WMV-2)
Family: Potyviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid
is filamentous,
flexuous with a length
of 730-765 nm. Axial
canal is indistinct.
Basic helix is obscure.
Purcifull & Batchelor, Bull.
Fla agric. Exp. Stn, 1977
Flexuous particles in leaf extract, negatively stained with
potassium phosphotungstate.
http://www.dpvweb.net/dpv/showfig.php?dpvno=293&
figno=05
Potyvirus-Watermelon
mosaic virus (WMV-2)
Family: Potyviridae
Hosts: Cucurbita
pepo, Cucumis melo,
C. sativus, Citrullus
lanatus and some
legumes — mosaic,
mottling, leaf shape
malformation.
Persistent symptoms.
Both Photographs by: Texas A&M Extension Service
http://aggie-horticulture.tamu.edu/publications/cucurbitproblemsolver/fruit/watermelon_mosaic.html
Potyvirus-Watermelon
mosaic virus (WMV-2)
Family: Potyviridae
Vector:
Virus is transmitted by
insects of the order
Hemiptera, family
Aphididae; Myzus
persicae, Aphis
craccivora, Aphis
citricola, Aphis
gossypii; at least 38
species of aphid in 19
genera transmit
watermelon mosaic
virus 2.
Lyle Buss, Univ.
of Florida
Green peach aphid, Myzus persicae
Lyle Buss, Univ.
of Florida
Cotton/Melon aphid, Aphis gossypii
Potyvirus-Watermelon
mosaic virus (WMV-2)
Family: Potyviridae
Viral diagnostic inclusions:
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and
scrolls in C-section
Laminated
aggregate
Amorphous cytoplasmic inclusions
Protein &
ribonucleo-protein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number
& aggregate with
some Potyvirus
infections
Inclusion of WMV in
pumpkin epidermal cells
(image courtesty of
R.Cullen and M Gooch)
Inclusions of WMV in pumpkin
(C.A. Baker)
Potyvirus-Zucchini yellow
mosaic virus (ZYMV)
Family: Potyviridae
Description:
Virions consist of a
capsid. Virus capsid is
not enveloped.
Capsid/nucleocapsid is
elongated with helical
symmetry. The capsid is
filamentous, flexuous
with a clear modal
length with a length of
750 nm and a width of
11 nm. Axial canal is
indistinct. Basic helix is
obscure.
V. Lisa
Istituto di Fitovirologia
applicata del C.N.R., Torino,
Italy
H. Lecoq
Station de Pathologie
Vegetale INRA, Montfavet,
France
Purified Zucchini yellow mosiac virus particles in uranyl
acetate.
Potyvirus-Zucchini yellow
mosaic virus (ZYMV)
Leaf deformation, shoe-stringing
and mosaic in naturally infected
zucchini squash.
Family: Potyviridae
Hosts: zucchini squash
(Cucurbita pepo),
muskmelon (Cucumis
melo), cucumber
(Cucumis sativus) and
watermelon (Citrullus
lanatus).
Vector: transmitted in
non-persistent manner
by Aphis citricola , A.
gossypii, Myzus persicae
and Macrosiphum
euphorbiae .
Fruit deformation in field-raised /infected zucchini squash after infection
by ZYMV ..
Potyvirus-Zucchini yellow
mosaic virus (ZYMV)
Family: Potyviridae
Hosts: zucchini squash
(Cucurbita pepo),
muskmelon (Cucumis
melo), cucumber
(Cucumis sativus) and
watermelon (Citrullus
lanatus).
Vector: transmitted in
non-persistent manner
by Aphis citricola , A.
gossypii, Myzus persicae
and Macrosiphum
euphorbiae .
Potyvirus-Zucchini yellow
mosaic virus (ZYMV)
Family: Potyviridae
Viral diagnostic inclusions:
Cytoplasmic cylindirical inclusions
Proteinaceous
Pinwheel and
scrolls in C-section
Laminated
aggregate
Amorphous cytoplasmic inclusions
Protein &
ribonucleo-protein
Irregular in shape
Vary in size
Vary in number
Nuclear inclusions
Proteinaceous
Most crystalline
Cytoplasmic microbodies
Healthy cells
Proteinaceous
crystals
increase in number
& aggregate with
some Potyvirus
infections
Florida Department of Agriculture
and Consumer Svcs.
Epidermal leaf strip of squash infected with ZYMV stained in OG.
(I=cylindrical inclusions, N=nucleus)

similar documents