Frangipani mosaic virus
Division of Mycology and Plant Pathology, Indian Agricultural Research Institute, New Delhi 110012, India
A. J. Gibbs
Research School of Biological Sciences, Australian National University, Canberra, Australia
Francki, Zaitlin & Grivell (1971).
- Temple tree mosaic virus
A virus with tubular particles 300 nm long and 18 nm in diameter. Sap transmissible.
No vector known; is spread in cuttings of infected frangipani (Plumeria spp.).
Restricted host range, grows best at 30-35°C.
In Plumeria acutifolia
the virus causes mosaic, ringspots, veinbanding and
In P. alba,
it causes ringspots, leaf distortion and necrosis.
No flower symptoms.
Common in eastern Australia and northern India.
Host Range and Symptomatology
Host range not yet tested extensively, but seems restricted. More species become
infected at temperatures above 25°C than below. At 35°C symptoms show in 3-6
days, at 22°C they take 2 weeks or more.
- Datura stramonium. Chlorotic, necrotic or black lesions develop in inoculated
leaves after 1-2 weeks in the glasshouse at 22°C. At 35°C, in controlled
environment cabinets, similar symptoms develop in 3 days
one strain causes
systemic necrosis along the veins and leaf margins.
- Nicotiana glutinosa. At 22°C inoculated leaves develop chlorotic lesions
in about 2 weeks
Not infected systemically.
- N. tabacum (tobacco) cvs Samsun, Virginia Gold or White Burley. Rarely infected
at 22°C. At 35°C all strains induce bright chlorotic or necrotic ringspots in
inoculated and systemically infected leaves
- N. clevelandii x N. glutinosa. Not infected at 22°C. At 35°C
inoculated leaves develop faint chlorotic lesions which become necrotic or develop
ringspots. Not infected systemically.
- Nicotiana glutinosa. Inoculated leaves give a good yield after 2-3 weeks at
- Datura stramonium is the most reliable assay species.
Three distinct strains from different provenances have been distinguished by the
symptoms they produce. They are the Adelaide strain (Adel)
(Francki et al., 1971
and the Allahabad (Ald) and Delhi (Del) strains (A. Varma & A. J. Gibbs,
unpublished data). Leaves of D. stramonium
kept at about 22°C develop
faint chlorotic lesions after inoculation with strain Adel, necrotic lesions after
inoculation with strain Ald, and chlorotic lesions, later becoming black, after
inoculation with strain Del. At 35°C symptoms developed more quickly and spread
more: strain Adel gave necrotic lesions, strain Ald gave lesions with chlorotic haloes
or ringspots, and strain Del gave spreading black necrotic ringspots and systemic veinal
and marginal necrosis. N. tabacum
cv. Virginia Gold was susceptible at 22°C
to strain Del only, showing chlorotic and necrotic local lesions. At 35°C in the
same tobacco cultivar, strain Adel gave faint necrotic ringspots, strain Ald gave bright
necrotic ringspots and strain Del gave large ringspots both in inoculated and in tip
Transmission by Vectors
No vector is known.
Transmission through Seed
Not transmitted through seed of D. stramonium
or N. tabacum
Particles of the virus are strongly immunogenic. They give flocculent precipitates
in tube precipitin tests, and form one band of precipitate in gel diffusion tests.
Properties, serological relationships and particle morphology place the virus in
The particles of frangipani mosaic virus are morphologically
indistinguishable from those of other tobamoviruses. The Adel, Ald and Del strains are
serologically closely related to each other. All three strains are related distantly to
cucumber virus 4,
cucumber green mottle mosaic virus
and an isolate of
sunn-hemp mosaic virus
from Queensland, Australia (but not one from West Africa); and even more distantly
tomato mosaic virus
ribgrass mosaic virus
Gibbs & A. Varma, unpublished data;
Francki et al., 1971
There was no
detectable serological relationship with Sammons
even though comparisons
of coat protein composition indicate a close affinity
(Description No. 184
Stability in Sap
Very stable. Sap from infected D. stramonium
was not infective after heating
to 95°C for 10 min, and lost 90% of its infectivity in 10 min at 90°C. The sap
was still infective after 10 weeks at room temperature, and at dilutions up to
The virus is easily purified from infected leaves of frangipani or N. glutinosa
by several methods. The following methods give good yields:
1. Francki et al. (1971),
McLean & Francki (1967)
Francki & McLean (1968).
Homogenise infected leaves of N. glutinosa in 1.5 volumes
of 0.2 M Na2HPO4, clarify by adsorption with charcoal and DEAE
cellulose and filter through Celite. Sediment the particles by centrifuging at 44,000
g for 90 min. Resuspend pellets in distilled water and emulsify with equal
volume of chloroform. Centrifuge at 12,000 g for 10 min. Collect aqueous
layer and sediment the particles by centrifuging at 16,000 g for 30 min.
Repeat chloroform extraction and sedimentation.
2. Based on
Varma, Gibbs & Woods (1970).
Triturate infected leaves mechanically
with 2 ml/g of neutral phosphate-ascorbate buffer (equal volumes of 0.1 M disodium
hydrogen phosphate and 0.05 M ascorbic acid). Add a quarter volume of chloroform,
emulsify, centrifuge at 8000 g for 10 min, collect supernatant fluid
and centrifuge for 1 h at 75,000 g. Resuspend the pellets in a small
quantity of the buffer. Further purify by rate zonal centrifugation at 45,000
g for 75 min in gradients of 10-40% sucrose.
Properties of Particles
In dilute solutions the virus sediments as a single component with sedimentation
coefficient (s20, w
) of 188 S (R. D. Woods, unpublished data).
The virus has rod-shaped particles about 300 nm long and 17 nm wide. The preparations
also contain shorter particles
(Francki et al., 1971
Particle CompositionNucleic acid:
The particles contain c.
Protein: Each subunit of the coat protein of strain Adel contains about 158
amino acid residues: Ala, 14; Arg, 11; Asx, 17; Cys, 1; Glx, 16; Gly, 9; His, 1; Ile,
11; Leu, 13; Lys, 4; Met, 0; Phe, 7; Pro, 4; Ser, 14; Thr, 13; Trp, 5; Tyr, 5; Val, 13
(Francki et al., 1971).
Of the other
whose coat proteins have been
analysed, Sammons opuntia virus has a composition most similar to that of frangipani
(Description No. 184).
Relations with Cells and Tissues
In the cytoplasm of infected parenchymatous cells of D. stramonium
the particles of frangipani mosaic virus aggregate as microcrystals of various shapes
Particles were not seen in mitochondria, chloroplasts or nuclei
although these organelles are not of normal appearance.
- Francki & McLean, Aust. J. biol. Sci. 21: 1311, 1968.
- Francki, Zaitlin & Grivell, Aust. J. biol Sci. 24: 815, 1971.
- McLean & Francki, Virology 31: 585, 1967.
- Varma, Gibbs & Woods, J. gen. Virol. 8: 21, 1970.
Leaf of Plumeria acutifolia infected with the Del strain.
Ringspots on leaf of Nicotiana tabacum cv. Virginia Gold systemically
infected with the Del strain and maintained at 35°C.
Local lesions induced by the Del strain in Datura stramonium leaf
maintained at 35°C.
Local lesions induced by the Adel strain in Datura stramonium leaf
maintained at 35°C.
Chlorotic local lesions induced by the Del strain in leaf of Nicotiana
glutinosa maintained at 22°C.
Electron micrograph of negatively stained particles of the Del strain. Bar
represents 200 nm. (Courtesy R. D. Woods.)
Electron micrograph of thin section of microcrystal in leaf of Datura
stramonium infected with the Del strain.