Skip to main content
ARS Home » Pacific West Area » Corvallis, Oregon » Horticultural Crops Research Unit » Research » Publications at this Location » Publication #177099

Title: TULIP VIRUS X (TVX) ASSOCIATED WITH LEMON BALM (MELISSA OFFICINALIS) VARIEGATION . FIRST REPORT OF TVX IN THE UNITED STATES.

Author
item TZANETAKIS, I - OREGON STATE UNIVERSITY
item MACKEY, I - OREGON STATE UNIVERSITY
item Martin, Robert

Submitted to: Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/14/2005
Publication Date: 7/20/2005
Citation: Tzanetakis, I.E., Mackey, I.C., Martin, R.R. 2005. Tulip virus x (tvx) associated with lemon balm (melissa officinalis) variegation . first report of tvx in the united states.. Plant Pathology. 54:562

Interpretive Summary: Lemon balm (Melissa officinalis) has been used for centuries as an ornamental and for its medicinal properties. One of the most popular clones shows bright variegation symptoms. We transmitted a virus from this clone to herbaceous hosts (Gomphrena globosa) in the greenhouse. The hosts developed necrotic lesions about five days later, which suggested a viral cause of the variegation. We observed viruslike particles that were approximately 500 x 13-14 nm in leaves of the inoculated plant. We then extracted virus-specific, double-stranded RNA that we cloned and sequenced. The sequence data revealed that the plant was infected with Tulip virus X (TVX), a virus not known to occur in the United States. We developed primers for detection of the virus and used these in reverse transcription- polymerase chain reaction (RT-PCR) to test for TVX in four variegated clones of M. officinalis from Oregon and Washington and in the symptomatic G. globosa indicators. The above mentioned plants all tested positive for TVX in the RT-PCR assay while non-inoculated G. globosa or asymptomatic M. officinalis plants were negative. This is the first report of TVX in association with the variegation in lemon balm and the first report, to our knowledge, for the presence of the virus in the United States.

Technical Abstract: Lemon balm (Melissa officinalis) has been used for centuries as an ornamental and for its medicinal properties. One of the most popular clones shows bright variegation symptoms. Mechanical inoculations onto Gomphrena globosa using variegated leaf tissue as the inoculum source resulted in development of necrotic lesions about five days post inoculation, which suggested a viral etiology of the variegation. Negatively stained leaf dips examined with an electron microscope revealed particles of approximately 500 x 13-14 nm. Double-stranded RNA was extracted from a variegated clone of the M. officinalis and cloned as described elsewhere (Tzanetakis et. al 2005). Sequence data (Genbank accession No AY842508-AY842510) revealed that the plant was infected with Tulip virus X (TVX). Oligonucleotide primers TVX 1F (5'GACAYTCTAACCCCTTCGC 3'), TVX 1R (5'GCCCTCTGTGGAAGTATCT 3') and TVX 2F (5' GAACAAGCACACCTCCACCA 3'), TVX 2R (5' AGTGTGGTTTTCCCGGC 3') were developed for detection of the virus and used in reverse transcription-polymerase chain reaction (RT-PCR) to test for TVX in four variegated clones of M. officinalis from Oregon and Washington and in the symptomatic G. globosa indicators. The above mentioned plants all tested positive for TVX in the RT-PCR assay while non-inoculated G. globosa or asymptomatic M. officinalis plants were negative. The amplicons were sequenced which confirmed their identity as TVX. This is the first report of TVX in association with the variegation in lemon balm and the first report, to our knowledge, for the presence of the virus in the United States.