Rice black streaked dwarf virus
Department of Botany, Faculty of Agriculture, Hokkaido University, Sapporo, Japan
First described by
Kuribayashi & Shinkai (1952).
A virus with isometric particles c. 75-80 nm in diameter. The virus is
not mechanically transmissible but is transmitted in a persistent manner by
planthoppers. Host range of the virus is restricted to species of Gramineae.
Infected plants show severe stunting, with neoplastic proliferations along the
veins. The disease causes serious damage to rice, maize, wheat and barley in Japan.
Causes stunting of plants, deformation of leaves, and white waxy or black-streaked
swellings along the veins in rice, maize, wheat, oat and barley
Host Range and Symptomatology
All known host plants are members of the Gramineae, in which 25 species,
including rice, maize, wheat, oat and barley can be infected by means of
- Oryza sativa (rice). Most japonica varieties of rice are very
susceptible; indica varieties are more or less resistant
(Morinaka & Sakurai, 1968).
Japanese paddy rice usually shows pronounced stunting
darkening of leaves, and twisting of the distal portions of young
leaves. The typical symptoms in rice are white waxy swellings along the veins
on the underside of the leaf blades, sheaths and culms; later they become
dark brown, forming black-streaked tumours of various lengths
Diseased plants produce poor heads or none at all; sometimes the heads are
retained within the sheaths. Dark brown blotches appear on some of the grains.
Symptoms appear after an incubation period of 14-24 days
Zea mays (maize). Infected plants are dwarfed with darkened
leaves. At an early stage of infection, white streaks appear along the veins
and white waxy swellings occur on the veins on the under surfaces of the leaves
Margins of old affected leaves split
Incubation period in
maize plants is 7-10 days
Triticum sativum (wheat), Avena sativa (oat) and
Hordeum vulgare (barley) are severely stunted
twisted leaves, sometimes with white waxy swellings on the veins on the
under surfaces of leaves and culms.
- Japanese rice varieties, wheat, oat and barley are good plants for
maintaining the virus, but maize cannot be used because it is a poor host
for the vector (see Assay species). For virus purification, rice and
maize plants are good sources. Virus contents are high in wheat and barley,
but contamination by bacteriophages sometimes occurs
(Kitagawa & Shikata, 1974).
- Maize (cv. Golden Cross Bantam) is highly susceptible to the virus
(Ishii, Yoshimura & Soejima, 1969),
showing obvious white streaks on the leaves
7-10 days after inoculation. When fed on maize, virus-carrying vector insects
(Laodelphax striatellus) usually die within 2-3 days and never lay eggs,
but about 80-100% of the plants may be infected. Thus diseased maize cannot be
used as a propagation species
(Ishii & Yoshimura, 1969;
Kitagawa & Shikata, 1973).
No strains reported.
Transmission by Vectors
Three planthopper species are known to transmit the virus in a persistent manner:
(Kuribayashi & Shinkai, 1952
and U. albifascia
No transmission occurs through the eggs
acquire the virus after feeding on infected rice plants for 30 min. Minimum
inoculation feeding time is about 5 min
Incubation period in
feeding insects is 7-35 days
after which the insects are
viruliferous until death. A large proportion of insects injected with extracts
from diseased plants or insects transmit the virus
(Kitagawa & Shikata, 1969a
By injecting insects serially with insect extracts, it was shown
that the virus multiplies in its vector
(Kitagawa & Shikata, 1974
Transmission through Seed
Transmission by Dodder
Rabbits receiving intravenous injections of purified preparations containing
particles 60 nm in diameter yielded antiserum with a titre of 1/8192 in the
ring precipitin test, and 1/1024 in the agar gel-diffusion test
(Luisoni et al., 1973
The morphology of the particles indicates that this virus probably belongs to
the same group as
maize rough dwarf
sugarcane Fiji disease
viruses. In host range and symptomatology, properties in vitro
and transmission by planthoppers, rice black streaked dwarf virus closely
maize rough dwarf virus,
and Luisoni et al. (1973)
that these two viruses are serologically related.
Stability in Sap
Thermal inactivation point (10 min) of the virus in rice extracts is 60°C.
Longevity in vitro
at 4°C is 7 days in rice sap, 6 days in insect
extracts. Infectivity survived more than 232 days in frozen rice leaves.
Dilution end-point is 10-5
in rice leaf extracts, 10-6
in insect extracts. The virus in crude rice leaf extracts retained its
infectivity after treatment at pH 5-9, or with 0.01 M ethylenediamine-tetraacetic
acid, 0.1% sodium deoxycholate, 40% carbon tetrachloride or 20% fluorocarbon,
but lost infectivity after treatment with 10-50% chloroform, 3-10% n
or 10-20% of a 1:1 mixture of chloroform and n
purified virus preparations were not inactivated by treatment with 50%
chloroform or 50% n
(Kitagawa & Shikata, 1973
Grind vector insects or diseased leaves of rice, maize, wheat or barley in
cold 0.1 M phosphate buffer, pH 7.0. Clarify the extracts with 30% carbon
tetrachloride, followed by differential centrifugation (8000 rev/min for
30 min, 20,000 rev/min for 60 min). Resuspend the pellets after high speed
centrifugation in 0.001 M phosphate buffer, pH 7.0. Further purification is
by sucrose density gradient centrifugation; infectivity is associated with a
single light-scattering zone. Virus concentrations are highest in barley and
in insect extracts
(Kitagawa & Shikata, 1969b
Properties of Particles
Virus particles in purified preparations are isometric, c.
60 nm in
but two kinds of particles, c.
75-80 nm and c
50-55 nm in diameter, occur in cells of infected plants and insects. Leaf
extracts in phosphate buffer or distilled water contain particles c.
nm in diameter without obvious outer projections, identical to those seen in
purified virus preparations. Leaves fixed in 2% osmium tetroxide or 2%
paraformaldehyde solutions before extraction yield large particles c.
75-80 nm in diameter with outer projections
Probably the virus
particles lose the outer projections during the purification procedures
Double-stranded RNA was detected by the acridine orange test described by
(Y. Kitagawa & T. Kodama, personal communication).
Relations with Cells and Tissues
Swellings on the leaves result from hyperplasia and hypertrophy of phloem cells
of infected plants. Inclusion bodies, about 6.5 µm in diameter and
stainable with giemsa, azure II, pyronin, trypan blue or acetocarmine, appear
within neoplastic cells
Ultrathin sections of
diseased leaves reveal the inclusions as granular structures (viroplasm) within
hypertrophied phloem cells
Small particles of c.
50-55 nm occur
in the viroplasms and large particles c.
75-80 nm are scattered in the
Large particles are sometimes seen arranged
within tubular structures
). Crystalline aggregates composed of large
particles are also found in the infected cells
In infected insect cells, large areas of the cell cytoplasm are occupied by
viroplasms, identical with those in infected plant cells. Large particles are
usually scattered in the cytoplasm around the viroplasms, or arranged within
tubular structures and in crystalline arrays
are found in cells of the fat bodies, salivary glands and intestines
maize rough dwarf virus
is reported to be related to rice
black streaked dwarf virus it seems to differ in being unable to infect Japanese
or Italian varieties of rice and in being transmitted through the egg of the
planthopper vector. Induction of swellings or black-streaked tumours on the
veins distinguishes rice black streaked dwarf virus from other viruses in rice.
- Bradley, Nature, Lond. 205: 1230, 1965.
- Ishii & Yoshimura, Ann. phytopath. Soc. Japan 35: 388, 1969.
- Ishii, Yoshimura & Soejima, Ann. phytopath. Soc. Japan 35: 361, 1969.
- Kashiwagi, Ann. phytopath. Soc. Japan 32: 168, 1966.
- Kitagawa & Shikata, Mem. Fac. Agric. Hokkaido Univ. 6: 439, 1969a.
- Kitagawa & Shikata, Mem. Fac. Agric. Hokkaido Univ. 6: 446, 1969b.
- Kitagawa & Shikata, Rep. Tottori mycol. Inst. 10: 787, 1973.
- Kitagawa & Shikata, Ann. phytopath. Soc. Japan 40: 329, 1974.
- Kuribayashi & Shinkai, Ann. phytopath. Soc. Japan 16: 41, 1952.
- Luisoni, Lovisolo, Kitagawa & Shikata, Virology 52: 281, 1973.
- Morinaka & Sakurai, Bull. Chugoku agric. exp. Stn Ser. E 2: 1, 1968.
- Shikata, in The Virus Diseases of the Rice Plant, compiled by Int. Rice Res. Inst., Johns Hopkins, Baltimore p. 223, 1969.
- Shikata, Ann. phytopath. Soc. Japan 39: 221, 1973.
- Shinkai, Bull. natn. Inst. agric. Sci., Tokyo Ser. C, 14: 1, 1962.
- Shinka, Ann. phytopath Soc. Japan 32: 317, 1966.
- Shinkai, Ann. phytopath. Soc. Japan 35: 318, 1967.
Rice plants, healthy (left), infected (right).
Black-streaked and white waxy tumours on leaves (right)
and culms (left and middle) of infected rice plants. (Courtesy
of Dr A. Shinkai.)
A wheat plant showing typical symptoms.
Streaks and white waxy proliferations on a maize leaf.
A maize leaf showing splitting of the leaf margin.
One of the insect vectors, Laodelphax striatellus. Male
(left), female (middle), 4th-instar nymph (right)
(Courtesy of Dr A. Shinkai.)
A dense viroplasm (Vp) in an infected maize leaf cell. Bar
represents 5 µm.
Low magnification electron micrograph showing inclusions (I) within
infected maize cells. Bar represents 5 µm.
Virus particles, 60 nm in diameter, in purified preparation,
stained with phosphotungstate. Bar represents 100 nm.
Large virus particles 75-80 nm in diameter within a tubular
structure, in dip preparation from OsO4-fixed leaves. Bar
represents 100 nm.
Ultrathin section of infected maize cell showing large particles
with outer coat and dense core (large arrows) at the periphery of a viroplasm,
and small particles (small arrows) within the viroplasm. Bar represents 100
Ultrathin section of cell from a viruliferous insect, showing a
crystal composed of large virus particles. Bar represents 100 nm.