Arch Virol (2003) 148: 2039–2045
Molecular evidence supporting the classiﬁcation of Hosta virus X
as a distinct species of the genus Potexvirus
M. H. Park and K. H. Ryu
Plant Virus GenBank, Division of Environmental and Life Sciences, Seoul Women’s
University, Seoul, Republic of Korea
Received November 29, 2002; accepted May 21, 2003
Published online July 17, 2003
Summary. A potexvirus, Hosta virus X (HVX-Kr), causing mosaic and mottle
symptoms was isolated from hosta plants (Hosta spp.) in Korea. The 3
2,711 nucleotides excluding the poly (A) tail were determined and shown to
include the partial viral replicase, triple gene block (TGB) 1 (26 kDa), TGB2
(13 kDa), TGB3 (8 kDa), and 23 kDa coat protein (CP) and the 3
region (NTR), typical of potexviruses. The CP gene of the type isolate of HVX
(HVX-U) was ampliﬁed by RT-PCR and its nucleotide sequence was determined.
The CPs of HVX-Kr and HVX-U had 100% and 98.9% identical amino acids
and nucleotides, respectively. Most of the regions of the genome HVX had over
50% nucleotide identical to other sequenced potexviruses. This is the ﬁrst report
of sequence information of HVX and molecular evidence supporting the virus as
a distinct species of the genus Potexvirus.
Species of Hosta, a genus in the family Liliaceae, have become popular throughout
the world as perennial garden and indoor ornamentals for shade-tolerant planting.
Recently, a number of varieties of hostas have been introduced in Korea for these
purposes. Five native hostas namely, H. capitata Nakai, H. clausa, H. longipes,
H. minor, and H. yingeri are cultivated in the southern areas of Korea with no
report of virus-like symptoms. Virus diseases reported elsewhere in the world on
cultivated hostas include Hosta virus X (HVX), Arabis mosaic virus, and Tomato
The nucleotide sequences of HVX-Kr and HVX-U reported in this paper will appear in
the EMBL, GenBank, and DDBJ sequence databases under the accession numbers AY181252
and AJ517352, respectively.