Arch Virol (1998) 143: 1637–1644
Watermelon bud necrosis tospovirus is a distinct virus species
belonging to serogroup IV
R. K. Jain
, H. R. Pappu
, S. S. Pappu
, M. Krishna Reddy
, and A. Vani
Department of Plant Pathology, University of Georgia, Tifton, Georgia, U.S.A.
Department of Entomology, University of Georgia, Tifton, Georgia, U.S.A.
Division of Biotechnology, Indian Institute of Horticultural Research, Bangalore, India
Accepted March 2, 1998
Summary. The nucleocapsid protein gene of a tospovirus infecting watermelon
in India was cloned and sequenced. Sequence analyses showed that the gene was
most closely related to those of watermelon silver mottle tospovirus (WSMV)
from Taiwan and peanut bud necrosis tospovirus (PBNV) from India, the two
deﬁnitive species of serogroup IV. Amino acid sequence similarity was 84% and
82% with WSMV and PBNV, respectively. On the basis of the sequence di-
vergence and the previously determined host range differences, the watermelon
tospovirus, designated as watermelon bud necrosis tospovirus, should be consid-
ered as a distinct species belonging to serogroup IV.
The genus Tospovirus of the family Bunyaviridae consists of several viruses
that are serious pathogens of peanut, tobacco, vegetables, ornamentals, and other
economically important crops [9, 11]. Tospoviruses are quasi-spherical in shape,
about 110 nm in diameter, and possess a characteristic lipid envelope. They
contain a segmented RNA genome of three single-stranded RNA molecules
(Small: S; Medium: M and Large: L) that are each bound by a nucleocapsid
(NP) protein. S and M RNAs are ambisense and L RNA is of negative sense
(reviewed in ). Tospoviruses are vectored by thrips in a propagative manner
(reviewed in ).
The nucleotide sequence data reported in this paper has been submitted to GenBank
under accession no. AF045067.