Barley yellow mosaic virus
College of Agriculture, University of Osaka Prefecture, Sakai, Osaka, Japan
Institute for Plant Virus Research, Ministry of Agriculture, Aoba Cho, Chiba, Japan
Described by Ikata & Kawai (1940).
A virus with slightly flexuous filamentous particles of two lengths, c. 275 and 550 nm, and
both 13 nm wide. It is sap-transmissible and soil-borne; the fungus Polymyxa graminis is thought
to be a vector. The only host known is barley. Found in Japan.
Causes mosaic in barley (Fig.1
sometimes the leaves show complete yellowing with necrotic patches;
plants are stunted. The severity of symptoms depends on the cultivar of barley
and the environmental
conditions. Symptoms are usually not produced above 18°C.
They usually appear in early spring but
tend to disappear as the weather becomes warmer.
Host Range and Symptomatology
The only host known is Hordeum vulgare
Transmitted through infective soil, and by inoculation of sap.
The species of plants tested but not infected include Triticum aestivum
(wheat), Avena sativa
(oat), Oryza sativa
and Nicotiana tabacum
- Hordeum vulgare (barley). The virus is transmissible to barley, though not readily, by
inoculation with plant sap and keeping test plants below about 18°C. Increased infectivity was
observed when inoculum was made by grinding diseased leaves in 10-3 M KCN, Na-DIECA, or
(Takanashi et al., 1967),
(Takahashi et al., 1968),
or 10-4 M p-nitrophenol
(Kusaba et al., 1971).
- Hordeum vulgare.
- No local lesion host is known. The virus may be assayed by finding the percentage of
Hordeum vulgare plants infected using different concentrations of inoculum.
No special strains have been described, but differences in varietal resistance of barley to
different virus isolates
(Takahashi et al.,1968
and in different infective soils
(Saito & Okamoto, 1964
Kusaba et al.,1971
) have been observed.
Transmission by VectorsKusaba et al. (1971)
suggested that a fungus, Polymyxa graminis,
is the vector of
the virus because (1) steamed soil became infective on addition of
resting spores of the fungus
collected from roots of barley naturally infected with the virus,
(2) virus transmission was not
prevented by treating resting spores of the fungus with 10% Teepol,
5% trisodium orthophosphate, or
at pH 2.3, (3) virus-free fungus acquired the ability to transmit when it was grown in plants
infected with virus by inoculation of sap,
(4) the infectivity of suspensions prepared from naturally
infected roots was closely related to the number of zoospores of the fungus that they contained.
Infectivity in air-dried soil was retained for over 5 years
(Yasu & Yoshino, 1964).
Transmission through Seed
Not found (Yasu & Yoshino, 1964
Transmission by Dodder
Serum from a rabbit injected intravenously, then intramuscularly,
with partially purified virus
reacted with the virus to a titre of 1/1280 in complement fixation tests
(Usugi & Saito, 1970
In complement fixation tests, barley yellow mosaic virus is serologically related to wheat
yellow mosaic and rice necrosis mosaic
(Usugi & Saito, 1970
). It resembles rice necrosis
wheat yellow mosaic
(Saito et al., 1966
wheat spindle streak mosaic
Hooper & Wiese, 1972
in its transmissibility through soil, its
particle morphology, and in inducing pinwheel-type inclusions and characteristic membranous network
structures in the cytoplasm of infected plant cells.
Stability in Sap
The dilution end-point is less than 10-2
(Kusaba et al.,1971
Yasu & Yoshino, 1964
The thermal inactivation point and longevity in vitro
are not known.
Infectivity of dried leaf tissue is retained for two years at 5-10°C
PurificationUsugi & Saito (1970)
: homogenize infected leaf tissue in 0.1 M citrate buffer (pH 7.0),
clarify by adding carbon tetrachloride, and concentrate by two or three cycles of differential
centrifugation. Two virus-containing bands form in sucrose density gradient centrifugation. Highly
purified virus preparations were obtained by equilibrium centrifugation in CsCl, only one band being
(Usugi & Saito, 1975
Properties of Particles
The ultraviolet absorption spectrum is typical for nucleoprotein, having a maximum at 265-270 nm
with a hump at 290 nm.
Buoyant density in CsCl: 1.29 g/ml
(Usugi & Saito, 1975).
) of barley yellow mosaic virus are slightly flexuous filaments 13 nm in diameter
and having two modal lengths of 275 and 550 nm; both lengths are found in leaf dips and in partially
purified virus preparations
Relations with Cells and Tissues
X-bodies can be found in cells of epidermal strips of infected leaves
). In ultrathin
sections, prominent membranous network structures, pinwheel-type inclusions, and loosely banded
aggregates of virus particles are often observed in the cytoplasm
(Saito et al.,1966
Barley yellow mosaic virus can be distinguished from other viruses with elongated particles
that infect barley in Japan by particle morphology and infectivity for
or C. quinoa
Barley stripe mosaic
(Atabekov & Novikov, 1971
soil-borne wheat mosaic
) viruses have straight rod-shaped particles and cause local lesions in the inoculated
leaves of the Chenopodium
spp. whereas barley yellow mosaic virus has more slender particles
and does not infect these hosts.
- Atabekov & Novikov, CMI/AAB Descriptions of Plant Viruses 68, 4 pp., 1971.
- Brakke, CMI/AAB Descriptions of Plant Viruses 77, 4 pp., 1971.
- Hooper & Wiese, Virology 47: 644,1972.
- Ikata & Kawai, Noji Kairyo Shiryo 154, 123 pp., 1940.
- Inouye, Nogaku Kenkyu 50: 117, 1964.
- Inouye, Ann. phytopath. Soc. Japan 34: 301, 1968.
- Inouye, Ann. phytopath. Soc. Japan 36: 186, 1970.
- Kusaba, Toyama, Yumoto & Tatebe, Spec. Bull. Tottori agric. exp. Stn 2, 208 pp., 1971.
- Miyamoto, Ann. phytopath. Soc. Japan 23: 199, 1958.
- Saito & Okamoto, Bull. natn. Inst. agric. Sci., Tokyo C 17: 75, 1964.
- Saito, Ueda & Inaba, Ann. phytopath. Soc. Japan 32: 87, 1966.
- Slykhuis, Phytopathology 60: 319, 1970.
- Takahashi, Inouye, Hayashi, Moriya, Hirao & Mitsuhata, Nogaku Kenkyu 52: 65, 1968.
- Takanashi, Saito & Iwata, Ann. phytopath. Soc. Japan 33: 43, 1967.
- Usugi & Saito, Ann. phytopath. Soc. Japan 36: 375, 1970.
- Usugi & Saito, Ann. phytopath. Soc. Japan 41: 87, 1975.
- Yasu & Yoshino, Bull. Saitama agric. exp. Stn 24: 1, 1964.
Barley leaves; (left) two leaves showing mottle with necrotic patches;
(centre) two leaves showing mottle;
(right) healthy leaf.
Virus particles from a partially purified preparation shadowed with chromium.
Bar represents 1 µm.
X-bodies in epidermal cells of barley. (N) nucleus; (X) X-body.
Section of infected leaf cell. (V) loosely banded aggregates of virus particles; (M)
membranous network structure. Bar represents 1 µm.