Henbane mosaic virus
D. A. Govier
Rothamsted Experimental Station, Harpenden, Hertfordshire, England
R. T. Plumb
Rothamsted Experimental Station, Harpenden, Hertfordshire, England
Described by Hamilton (1932)
& Bartels (1970)
- Selected synonyms
- Hyoscyamus virus III (Rev. appl. Mycol. 17: 64)
- Hyoscyamus virus I (Rev. appl. Mycol. 17: 52)
- Atropa mild mosaic virus (Rev. Pl. Path. 50: 2197)
An RNA-containing virus with filamentous particles, 800 or 900 nm long (see
below) that infects mainly solanaceous hosts. It is readily transmitted by
inoculation of sap, and by aphids in the non-persistent manner.
Causes mosaic diseases in Hyoscyamus niger, Datura
, and strains have been isolated from Atropa
Reported only from England, Germany and Italy although it may be widespread
in solanaceous weed hosts. Not reported naturally infecting tobacco.
Host Range and Symptomatology
Host range mainly in the Solanaceae
. Readily transmitted by
inoculation of sap to:
- Diagnostic species
- Hyoscyamus niger (Fig.1, Fig.2),
Nicotiana tabacum (Fig.3), N.
glutinosa and N. rustica. Inoculated leaves usually develop poorly
defined chlorotic or necrotic lesions. Vein-clearing of the young leaves is
followed by a green or yellow-green systemic mosaic, often with dark green
blistering and sometimes with necrotic spots or rings.
- Nicotiana sylvestris. Most strains give necrotic lesions, often in
the form of rings, on the inoculated leaves (Fig.5); systemic mottling and
necrosis develop later.
- Datura stramonium. Severe systemic mosaic with leaf-narrowing,
blistering and malformations (Fig.6).
- Chenopodium amaranticolor. Some strains give circular chlorotic
local lesions with necrotic centres; not systemic.
- Solanum demissum x S. tuberosum A-6. Necrotic local
- Propagation species
- Nicotiana tabacum cv. Xanthi-nc may be used for maintaining the virus
and is a good source of virus for purification.
- Assay species
- S. demissum x S. tuberosum A-6, N. sylvestris.
Many minor variants have been obtained from the original isolate (Watson,
) and these and the strains isolated from naturally infected Atropa
(Bode, Brandes & Paul, 1969
; Harrison & Roberts, 1971
Govier & Woods, 1971
spp. (Bradley, 1952
; Lovisolo &
) and Physalis alkekengi
(Lovisolo & Bartels, 1970
differ from the type virus in their reactions on some hosts.
Transmission by Vectors
Most strains are transmitted readily by Myzus persicae; M. ascalonicus,
and Macrosiphum euphorbiae
are also vectors
(Watson & Roberts, 1939
; Doncaster & Kassanis, 1946
). All instars can
transmit. Aphids can acquire the virus in 10 sec and inoculate it in a similar
period. There is no latent period. Some feeding aphids retain infectivity for
6 hr and starving aphids for 24 hr. Not transmitted to progeny aphids.
Transmission through Seed
Transmission by Dodder
Strongly immunogenic. The virus gives flocculent precipitates in
tube-precipitation tests and is readily detected in tobacco sap by
slide-agglutination tests. Agar gel-diffusion tests fail with intact virus.
Strains occurring naturally in Atropa belladonna, Datura
are closely related serologically to isolates derived
from the original henbane culture. In plant-protection tests, strains protect
against one another. Discrepancies in particle length determinations, and the
possibility that some cultures of henbane mosaic virus were contaminated with
potato virus Y
, cast some doubt (Govier & Woods, 1971
) on reports that
henbane mosaic virus is distantly related serologically to several viruses of
the potato virus Y group
), but the serological relationship
with potato virus Y has now been confirmed (D. A. Govier, unpublished). Distant
serological relationships have also been reported with Columbian datura virus
(Kahn & Bartels, 1968
) and pokeweed mosaic virus
(Shepherd, Fulton &
Stability in Sap
In tobacco or Datura stramonium
sap, the thermal inactivation point
(10 min) is about 60°C, dilution end-point about 10-6
, and most
infectivity is lost in a few days at 20°C.
The following method (D. A. Govier & B. Kassanis, unpublished) gives
infective preparations in which the particles are less aggregated than in
preparations made by other methods. Homogenize leaves in a cooled blender
with 0.1 M ethylenediamine-tetraacetate pH 7.6 containing 0.01 M
Na-diethyldithiocarbamate (DIECA), 2 ml/g tissue. Squeeze the sap through
muslin, clarify by centrifuging for 30 min at 15,000 g
for 18-24 hr against 10 vol of 0.005 M DIECA and reclarify. Shake the
supernatant fluid for 5-10 min with 1/4 vol of chloroform, centrifuge, and
subject the aqueous phase to 2 or 3 cycles of differential centrifugation
(50 min at 100,000 g
, 10 min at 15,000 g
resuspending virus pellets in 0.01 M borate pH 7.5. Aggregation is largely
prevented by leaving pellets covered with buffer overnight at 5°C before
resuspending, by concentrating only slightly when resuspending the first
high-speed pellets and, when a large weight of leaves is used, by infiltrating
the leaves with extracting solution under vacuum before homogenizing them.
About 30 mg of virus are obtained from 1 kg of leaves.
Properties of Particles
Sedimentation coefficient (s20,w
) at infinite dilution:
about 160 S.
Particles are filamentous, 12-13 nm wide and helically constructed, their
length and appearance depending on the conditions of extraction (Govier &
). When magnesium ions are absent, the particles are flexuous and
have a normal length of about 800 nm (Fig.7
), but when magnesium is present,
the particles are straight or only slightly flexuous and have a normal length
of about 900 nm (Fig.8
Molar percentages of nucleotides G26; A29; C27; U18 (J. M.
Protein: Subunits have molecular weight of about 3.2 x 104
(J. M. Carpenter, unpublished).
Relations with Cells and Tissues
Details reported for the atropa mild mosaic strain (Harrison & Roberts,
) have been confirmed for the type strain (R. T. Plumb & D. A. Vince,
unpublished). Pinwheel inclusions occur in sections of systemically infected
tissue and in leaf-dip preparations, often with virus particles lying parallel
to their long axis. The pinwheel lamellae have characteristic striations with
a spacing of about 5 nm. Crystalline material with a honeycomb-like structure
occurs in sections of infected cells. Virus-like particles show in leaf sections
fixed in glutaraldehyde and osmic acid (Harrison & Roberts, 1971
), or better
in sections fixed in osmic acid alone (Plumb & Vince, 1971
General similarity of properties, the presence of pinwheel inclusions in infected
cells and distant serological relationships, place this virus in the
potato virus Y group
, although its particles are longer than those of other viruses in the
group. In contrast to potato virus Y
, it infects Datura stramonium
is readily distinguished from tobacco etch virus
because it does not produce
- Bartels, Phytopath. Z. 49: 257, 1964.
- Bode, Brandes & Paul, Jber. biol. BundAnst. Land- u.Forstw. Braunschweig 1968: A61, 1969.
- Bradley, Ann. appl. Biol. 39: 78, 1952.
- Doncaster & Kassanis, Ann. appl. Biol. 33: 66, 1946.
- Govier & Woods, J. gen. Virol. 13: 127, 1971.
- Hamilton, Ann. appl. Biol. 19: 550, 1932.
- Harrison & Roberts, J. gen. Virol. 10: 71, 1971.
- Kahn & Bartels, Phytopathology 58: 587, 1968.
- Lovisolo & Bartels, Phytopath. Z. 69: 189, 1970.
- Plumb & Vince, J. gen. Virol. 13: 357, 1971.
- Shepherd, Fulton & Wakeman, Phytopathology 59: 219, 1969.
- Watson, Rep. Rothamsted exp. Stn 1967: 123, 1968.
- Watson & Roberts, Proc. R. Soc. B 127: 543, 1939.
Diseased plant of Hyoscyamus niger.
Systemically infected leaf of Hyoscyamus niger.
Systemically infected leaf of Nicotiana tabacum cv. Xanthi-nc.
Inoculated leaf of Solanum demissum x S. tuberosum A-6,
showing local lesions. (Courtesy R. Bartels.)
Inoculated leaf of Nicotiana sylvestris, showing local lesions.
Systemically infected leaf of Datura stramonium.
Virus particles from a purified preparation stained with phosphotungstate.
Bar represents 100 nm.
Virus particles from the same preparation after adding Mg ions. Stained
with phosphotungstate. Bar represents 100 nm.