Potato leafroll virus
Department of Virology, State Agricultural University, Wageningen, The Netherlands
- Described by
Quanjer, Van der Lek & Oortwijn Botjes (1916).
- Potato phloem necrosis virus
A virus with isometric particles about 24 nm in diameter. It has
a narrow host range, is not sap transmissible, but is transmitted
by about 10 species of aphids in the persistent manner. Common
wherever potatoes are grown.
Causes prominent rolling of the leaves of potato and a stiff
upright habit of the plants
There is necrosis of the
phloem and accumulation of carbohydrates in the leaves.
World wide, wherever potatoes are grown.
Host Range and Symptomatology
Hosts are mainly in the Solanaceae, but some non-solanaceous
plants such as Amaranthus caudatus, Celosia argentea, Gomphrena
and Nolana lanceolata
(Natti, Kirkpatrick & Ross, 1953
- Physalis floridana. Leaves show interveinal chlorosis; plants
show variable amounts of stunting, depending on strain and
- Datura stramonium. Interveinal chlorosis.
- Solanum tuberosum (potato). Several varieties may
react with the characteristic symptoms described above.
- Propagation species
- Plants and tubers of Solanum tuberosum are convenient
for maintaining isolates, Physalis floridana
(Kojima et al., 1969)
and Datura stramonium
(Peters & Van Loon, 1968)
are used for purification.
- Assay species
- Physalis floridana is used to test the transmitting ability
of aphids that have acquired the virus from plants or have been
infected by injection. This plant may also give interveinal
chlorosis upon infection with other viruses persistent in aphids
Strains are distinguished on the basis of severity of reaction
of P. floridana
Webb, Larson & Walker (1951)
distinguished five strains;
Transmission by Vectors
Transmissible by more than 10 aphid species in the persistent
(Kennedy, Day & Eastop, 1962
seems to be the most efficient vector. All instars can acquire
and transmit, but nymphs transmit more efficiently than adults.
Acquisition and inoculation feeding periods of 1 day are necessary
to obtain high levels of infection. There is a latent period longer
than half a day. Virus is retained by the vector for its whole life
span. The ability of the aphid to transmit depends on the dose of
Multiplication of the virus in the aphid has been reported
(Stegwee & Ponsen, 1958
to obtain evidence of multiplication.
Transmission through Seed
Probably does not occur.
Transmission by Dodder
Reported for Cuscuta subinclusa
There are no reports of antisera to potato leaf roll virus
having been prepared.
In plant protection tests, infection with avirulent strains
protects plants from virulent strains
(Webb et al., 1952
In transmission experiments, single M.
could acquire and transmit a virulent strain after
acquisition and transmission of an avirulent strain.
Duffus & Gold (1969)
did not detect any serological reaction between potato
leaf-roll virus and
beet western yellows virus
antiserum using the
infectivity neutralization and membrane feeding technique.
Stability in Sap
In extracts of aphids and sap of Physalis floridana,
thermal inactivation point (10 min) is about 70°C and dilution
end-point about 10-4
; longevity in sap is about 4 days at
2°C, and in aphid extracts between 12 and 24 h at 25°C
(Murayama & Kojima, 1965
be stabilized by adding reducing agents.
Two methods have been developed, one to purify the virus from
aphids and the other from plant material. Both methods yield small
amounts of virus, but more was obtained from plant material.
1. Peters (1967a,
Extract aphid homogenates in 0.01 M
phosphate buffer with an equal volume of chloroform twice at
pH 5.0 and twice at pH 7.0. Pool the two pH 7.0 extracts and
sediment by high speed centrifugation. Resuspend the pellet in
0.01 M phosphate (pH 7.2) and mix with an equal volume of
2.5 M K2HPO4 - KH2PO4
(pH 7.5), and 0.8 volume of a 1:2 mixture of butoxy-ethanol
and ethoxy-ethanol. Extract the virus from the interphase obtained
after low speed centrifugation. Clarify the suspension and purify
the virus further by centrifugation in sucrose density gradients.
Do all steps at 0-4°C.
2. Kojima et al. (1969).
Emulsify extracts from frozen
Physalis floridana plants with a mixture of chloroform and
n-butanol. Centrifuge at high speed, resuspend the pellet
in 0.01 M phosphate buffer and emulsify the suspension with
fluorocarbon (Daifron S-3). Centrifuge again at high speed and
fractionate on a sucrose gradient. Do all steps at 0-4°C.
Properties of Particles
Particles are isometric, c.
24 nm in diameter
Relations with Cells and Tissues
The virus seems to be restricted to the phloem, in which virus
particles have been observed by electron microscopy
(Kojima et al., 1969
The virus may be confused with other viruses that are transmitted
by aphids in the persistent manner and have host ranges overlapping
that of potato leafroll virus
of these viruses were found contaminating a potato leafroll virus
- Day, Aust. J. biol. Sci. 8: 498, 1955.
- Duffus, Phytopathology 54: 736, 1964.
- Duffus & Gold, Virology 37: 150, 1969.
- Harrison, Virology 6: 265, 1958a.
- Harrison, Virology 6: 278, 1958b.
- Kennedy, Day & Eastop, A conspectus of aphids as vectors of plant viruses, London, Commonwealth Institute of Entomology, 1962.
- Kojima, Shikata, Sugawara & Muryama, Virology 39: 162, 1969.
- MacCarthy, Phytopathology 44: 167, 1954.
- MacKinnon, Virology 20: 281, 1963.
- MacKinnon, Can. J. Bot. 43: 509, 1965.
- Murayama & Kojima, Ann. phytopath. Soc. Japan 30: 209, 1965.
- Natti, Kirkpatrick & Ross, Am. Potato J. 30: 55, 1953.
- Peters, Virology 26: 159, 1965.
- Peters, Virology 31: 46, 1967a.
- Peters, Meded. Fonds Landbouw Export Bureau 45, 100 pp., 1967b.
- Peters & Van Loon, Virology 35: 597, 1968.
- Quanjer, Meded. LandbHoogesch. Wageningen 6: 41, 1913.
- Quanjer, Van der Lek & Oortwijn Botjes, Meded. LandbHoogesch. Wageningen 10: 1, 1916.
- Rozendaal, Meded. ned. aig. KeurDienst LandbZaken Aardappelpootg. 8: 94, 1952.
- Stegwee & Ponsen, Entomologia exp. appl. 1: 291, 1958.
- Webb, Am. Potato J. 32: 173, 1955.
- Webb, Larson & Walker, Am. Potato J. 28: 667, 1951.
- Williams, Diss. Abstr. 27: 2784, 1957.
Plants of Solanum tuberosum cv. Meerster,
(left) infected, (right) healthy.
(Photo courtesy A. Rozendaal.)
Physalis floridana, (left) healthy,
Virus particles from a purified preparation, stained
with 2% phosphotungstate. Bar represents 100 nm. (Photo courtesy M. Kojima.)