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*NEW*
MYTH - HVX spreads easily/HVX is
difficult to spread.
FACT - Which is it? Dr. Lockhart,
who is credited with discovering HVX has said it is difficult to
spread, while others say it is easy to spread. It depends on the
point of view. A virologist considers it difficult compared to
other viruses which can spread more easily because they are
transmitted by insects or other vectors. Gardeners and nursery
owners on the other hand feel that it spreads easily because it
is easy to spread it while doing the things they normally do
with the plants, like cutting flower scapes, damaged leaves, or
dividing. In this case there is no myth because both are true.
*NEW*
MYTH - Some hostas are immune.
FACT - The basis for this myth (and
it is a dangerous myth at that) is a study done by Dr. Lockhart.
In this study several varieties were not infected despite
numerous tries. The report on this study in The Hosta Journal
did unfortunately use the word "immune" to describe
these plants. Testing for this "immunity" was not
exhaustive, and the use of the word was clearly a case of
jumping the gun. Since this study, one of the "immune"
cultivars has tested positive (not the actual plant from the
study), and this should be taken as evidence that these
cultivars are not to be considered truly immune unless further
testing proves them so. In a sidelight, articles mentioning this
"immune" list have started adding plants that were not
in the original study. One included 'Gold Standard', which is
one of the most easily and heavily infected in the marketplace.
No hostas should be considered immune at this time.
MYTH
- Plants infected with a virus may recover.
FACT - Viruses do not just
disappear, nor does a plant "fight off" an infection.
The virus is permanent and will be with the plant until it dies.
For practical purposes in the garden and nursery, there are no
cures for viruses.
MYTH - Hostas from Tissue Culture
will not have viruses.
FACT – If a hosta has a virus
before going into tissue culture, the virus will be propagated
along with the plant. Many infected hostas in the marketplace
were tissue-cultured. Plants that were clean after the tissue
culture process may also be infected when being grown on. Labs
are beginning to test all propagating material so in the near
future tissue cultured hostas from those labs will be clean.
MYTH - All hosta cultivars will
exhibit the same symptoms if infected with the same virus.
FACT – Symptoms can vary
considerably with the same virus, and different strains of a
virus may cause different symptoms.
MYTH - All mottled foliage in
hostas is caused by viruses.
FACT – Mottling patterns in
hostas can have a variety of causes, some of them environmental,
and many have causes which we do not yet understand. 'Xanadu
Paisley' has been repeatedly tested and despite its similarity
to HVX symptoms has yet to be shown to be infected with any
diseases. Old plants like 'Cynthia' and 'Filigree' also have no
known cause for their mottled appearance and have never been
know to pass this trait to other plants.
MYTH - Viruses
will kill, or at least severely inhibit growth of the host
plant.
FACT – Eventually, some
deterioration in the health of the plant can occur, but a plant
may survive for many years when infected with a virus. Different
viruses affect the plant's health at different rates, but some
effects may go unnoticed.
MYTH - If
symptoms disappear after showing up in a previous year the plant
has either cured itself or didn’t have a virus in the earlier
year.
FACT – The expression of virus
symptoms can disappear, but this does not mean the plant is
cured. The virus is still present in the plant and still able to
infect other plants. Sometimes this can be due to environmental
factors that might reduce the rate a virus replicates thus
preventing a high enough population, or titer, to effect
expression.
MYTH - Removing a leaf showing
infection, or dividing out the portion of the hosta showing
symptoms will help cure the plant.
FACT – Removing some symptomatic
tissue will have no real effect in "curing" a plant of
a virus. The virus is already in all or most all parts of a
plant by the time symptoms show.
MYTH - All plants infected with HVX
will show symptoms immediately.
FACT – To the contrary, many
plants in Dr. Lockhart's study did not show symptoms after three
years despite testing positive for infection. We do not know if
they will ever show symptoms, but they are infectious in this
state.
MYTH - If the symptoms have not
spread to nearby plants the virus is safe.
FACT – If a virus is "safe",
how did that plant catch it? The only way to tell if HVX has
spread to other plants is through ELISA or other more sensitive
scientific testing. It may be years before infected plants show
symptoms.
MYTH - If a plant doesn’t show
symptoms it doesn’t have a virus.
FACT – It can take years for an
infected plant to show symptoms. During this time it very much
can infect other plants. Only careful scientific testing can
determine if a plant that does not show symptoms is infected
with a virus - there is no way for the gardener or nursery owner
to tell.
MYTH - HVX is the only virus
affecting hostas.
FACT – There may be more than ten
viruses currently known to be found in hostas. HVX is now the
most common by far, but Impatiens Necrotic Spot, Tobacco Rattle
Virus, and Tomato Ringspot Virus have been frequently identified.
Some as yet unidentified viruses have appeared also.
MYTH - Symptoms of Hosta Virus X
look attractive.
FACT – Actually, this is not
really a myth. The effects of HVX on some hostas can be
attractive to many, thus heightening the risk of introducing the
virus into the home garden. In addition to the mottling, these
symptoms can include making the infected plant more compact and
more glaucous. Nursery professionals and home gardeners alike
have actually named HVX-infected hostas and offered them as new
varieties.
MYTH - Virused hostas are worth
more money than healthy hostas.
FACT – Well, does this really
make any sense? If you buy a hosta for $5 and infect it with a
disease as common and widespread as HVX, how could it possibly
be worth more? When infected with an incurable disease, it
should be thrown away because it is no longer worth anything.
Putting a different name on it once it is infected doesn't
really change this.
MYTH - If
we pretend the virus doesn’t exist it will go away.
FACT – If we ignore the presence
of Hosta Virus X in our gardens or nurseries, it will continue
to spread until many more plants have it. In time, the number of
infected plants will increase beyond any hope of eliminating the
virus. It is irresponsible to keep the virus around, because it
can infect other plants and spread itself. All plants exhibiting
HVX symptoms must be destroyed immediately to prevent further
infection, and in nurseries all plants in a batch that had
symptomatic individual plants must be also considered infected
and likewise destroyed.
MYTH - Talking about HVX and other
diseases will ruin hosta gardening.
FACT – While it may be unpopular
in the short term, allowing incurable diseases to run unchecked
through nurseries and gardens will certainly cause worse
problems down the road. The long-term impact of disease-filled
gardens on their owners will surely be a negative one and far
outweigh any short-term effects of facing our problems now. A
healthy garden is a source of joy to the gardener, but a garden
full of diseases and other problems will never provide the same
enjoyment, and if it gets worse every year we will lose our
enthusiasm.
MYTH - People don't want to know
about HVX.
FACT – It is not a pleasant
subject, but as adults we all understand that life isn't perfect.
The world contains many harmful organisms, and some of these do
affect hostas. We can face the issues of plant health when we
need to. We understand that sometimes there are outbreaks of a
particular disease that require our special attention. We don't
really want to know, but we have to know to keep our plants
healthy. We don't want that information kept from us when the
time comes that we need it.
MYTH - Viruses are a "grower
problem" and not a cause for concern among gardeners.
FACT – Hostas infected with HVX
or other viruses ceased to be simply a "grower problem"
when the retailers sold them to gardeners. Thousands of
virus-infected plants have already been sold at the retail level,
and many gardens now harbor virus-infected hostas. All gardeners
should be aware of HVX and other viruses and be careful to avoid
spreading them to other plants and to other gardens.
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