RMV... What do you do after?
Moyesii
spring. It has been growing well, but now shows clear signs of RMV.
What do you do after you find that one of your roses is virused? Do
you shovel prune or let it live its life out? The problem for me is
that most climbers take at least 3 years to establish and by that
time, I'm not sure what to expect from a virused rose in terms of
vigor and general performance. On the other hand, the plant looks to
be doing fine, and I'd hate to toss it.
Cass
<moy...@aol.com> wrote:
Depends on how the plant looks. I have a few that perform, flower and
are reasonably disease resistant. But if it gives me any problems, I
kill them fast.
Tim Tompkins
enough that the root systems grow togather.
Many plant virus are spread by this means and the only way to ensure that
the disease does not spread is to be absolutely certain that the infected
plants roots don't involve other plants.
Tim
"Cass" <cass666...@attbi.com> wrote in message
news:060820030027472453%cass666...@attbi.com...
Theo Asir
to back that up.
Several of my plants are virussed
and grow close to plants that are
non virused.
As far as I know the only real
chance of virus spread is if you
don't sterilize your shears.
--
Theo in Zone 5
Kansas City
"Tim Tompkins" <timp...@frii.com> wrote in message
news:3f30fbc0$0$200$7586...@news.frii.net...
Moyesii
> enough that the root systems grow togather.
>
>
I've never heard of this happening before. Doesn't this imply that the
roots of different plants would somehow have to graft to each other?
It seems unlikely.
Shiva
wrote:
>RMV can be tranmitted to another rose by the root system if they are close
>enough that the root systems grow togather.
>
>Many plant virus are spread by this means and the only way to ensure that
>the disease does not spread is to be absolutely certain that the infected
>plants roots don't involve other plants.
>
>Tim
Tim--while I am the first person to appreciate the power of an
authoritative tone, here yours is misplaced. This is nonsense. Post
proof or recant, please.
Shiva
<ta...@nospam.sfsarch.com> wrote:
>
>As far as I know the only real
>chance of virus spread is if you
>don't sterilize your shears.
NO way, Theo! You are telling me I can spread Rose Mosaic
Virus from my Sonia Rykiel to my other roses if I don't sterilize my
felcos?? Here is where I ask you to cite your source. If this is true
then RMV is a much bigger deal than I thought.
Anne Lurie
http://members.aol.com/mmmavocad3/Mosaic.html (It's from 1993, though, so
there could have been discoveries made since then.)
Anne Lurie
Raleigh, NC
"Theo Asir" <ta...@nospam.sfsarch.com> wrote in message
news:2c27bade3df537f78e90318c918526a8@TeraNews...
Unique Too
>Here's a link to an article from the Central Florida Heritage Rose Society:
>http://members.aol.com/mmmavocad3/Mosaic.html (It's from 1993, though, so
>there could have been discoveries made since then.)
I think Dr. Manners is considered the ultimate authority on RMV and to my
knowledge the article you mentioned is still the most current information
available. He lists an email address on his site, if anyone cares to ask him.
Or perhaps he will see this message title and respond here. He has been known
to post here on occasion.
Julie
Theo Asir
I can't find my original source but
if you google, a few sites do recommend
this as a conservative precaution.
http://www.uri.edu/ce/factsheets/sheets/rosediseases.html
http://www.urbanext.uiuc.edu/roses/disease-disease.html
--
Theo in Zone 5
Kansas City
"Shiva" <hyp...@cotse.net> wrote in message
news:3c9065730ba6bb07...@free.teranews.com...
Shiva
wrote:
>RMV can be tranmitted to another rose by the root system if they are close
>enough that the root systems grow togather.
>
>Many plant virus are spread by this means and the only way to ensure that
>the disease does not spread is to be absolutely certain that the infected
>plants roots don't involve other plants.
>
>Tim
Here is what Malcolm Manners says about contagiousness of RMV:
"Means of Transmission
RM is believed to be non-contagious in the field, except possibly
through rare natural root grafts. There is no evidence that it ever
spreads naturally in the garden or nursery, or through pollen, seed,
or seedlings (2). Extensive tests also have failed to transfer RM
mechanically (e.g., on pruning tools, grafting knives, etc.) (3). The
only known means for transmitting the disease is by vegetative
propagation. Cuttings rooted from infected plants, or budded plants
produced from infected scions or rootstocks, will be infected in
virtually every case. The disease is systemic, so the entire plant is
infected, whether or not all of the branches show symptoms. A plant
which is infected at the time of propagation will remain infected
throughout its life, and a healthy plant at the time of propagation
should remain healthy for its entire life, unless an infected scion is
budded or grafted onto it."
Thanks for the link, Anne. I guess I am safe keeping my Sonia Rykiel.
tim, where do you get this stuff?
Henry Kuska
http://home.neo.rr.com/kuska/mis_info_about_virus.htm
--
Henry Kuska, retired
ku...@neo.rr.com
http://home.neo.rr.com/kuska/
Cass
<ku...@neo.rr.com> wrote:
> See the following link:
>
> http://home.neo.rr.com/kuska/mis_info_about_virus.htm
This is all rather annoying, since, as Dr. Kuska points out, none of us
can prove that *any* of our roses is virus-free. I share others'
concerns about spreading virus through pruning, especially winter
pruning. For no reason other than pure conjecture, I tend to think that
the pollen and root transmission is a remote threat I can live with.
Have any hybridizers reported virused seedlings produced from virused
pollen and/or seed parent?
BTW, I can't understand why my Bonica image was picked up by Google in
the rose mosaic virus images. Weird.
Henry Kuska
produced from virused
pollen and/or seed parent?" was answered in my post. Yes.
"Ping Lim, an All American Rose winning hybridizer, stated in
rec.gardens.roses that he has observed virused seedlings from virused
parents.
He is not the first hybridizer to report that some of his seedlings
were virused. Harvey Davidson reported in 1988 (Davidson, H., The American
Rose Magazine, volumn 29, page 16, (1988)) that some of his seedlings were
virused and that he had heard, in a recent lecture, Dr. Dennison Morey state
that rose mosaic can be transferred through pollen. Dr. Morey was at one
time the head of the breeding program for Jackson and Perkins."
Shiva
wrote:
>Cass, your question: "Have any hybridizers reported virused seedlings
>produced from virused
>pollen and/or seed parent?" was answered in my post. Yes.
>"Ping Lim, an All American Rose winning hybridizer, stated in
>rec.gardens.roses that he has observed virused seedlings from virused
>parents.
It remains a fact that we have seen no evidence at all--so far--that
Rose Mosaic Virus can spread from one plant to another in our gardens.
Henry Kuska
far--that Rose Mosaic Virus can spread from one plant to another in our
gardens."
My reply. Oh?
http://www.rdrop.com/~paul/tom_virus.html
Unique Too
two items of misinformation I start to doubt the reliabilty of the rest of
their information. Cleaning your pruners between plants isn't a bad idea, but
since symptoms of RMV may not show up for several years you would have to
disinfect everytime you work on a different plant.
"Mosaic:
<snip>
Control:
<snip>
Plant virus resistant roses if possible. "
There is no such thing as an RMV resistant rose. If you graft an infected root
to a healthy cutting, it will be infected.
"Rosette and Witches Broom:
<snip>
Control:
The exact cause of this disease is unknown. Infected plants cannot be cured.
Try to control insects, particularly leaf hoppers and plant hoppers....."
RRD is caused by a mite. And there is an insecticide which kills the mites
that spread the disease. See Ann Peck's site for more details.
http://web.ntown.net/~apeck/index.htm
Julie
Shiva
wrote:
>Shiva said: "It remains a fact that we have seen no evidence at all--so
>far--that Rose Mosaic Virus can spread from one plant to another in our
>gardens."
>
>My reply. Oh?
>http://www.rdrop.com/~paul/tom_virus.html
Oh please, Henry! You are a scientist, no? Retired, maybe, but once a
scientist always a scientist. Yet you are claiming that a second-hand
tale told by Ann Mansker about a SINGLE study--in other words a study
that has not been replicated anywhere, ever--in which some rows of
multiflora, some virused, some not, were planted close to one another
and trimmed with hedgetrimmers, and in a couple of years showed a ONE
to TWO percent incidence of the virus in plants ALLEGEDLY virus free
at the beginning of the study
is proof that Rose Mosaic Virus can spread in our gardens?
Is this what you are saying?
In addition to all the tacit problems with this statement, how do we
know--how did THEY know the original plants that were allegedly virus
free really were?
Thanks for the information, and please take this in the spirit in
which it is offered--that of a good lively debate.
I have noticed in Gardenweb and other fora that there are people who
get very, shall we say, emotional about RMV, and they tend to be
alarmists who love to exaggerate its ill effects.
It is going to take more than the above to convince me that it is
going to spread in my garden.
Shiva
Correction-- should read "Yet you are claiming that a second-hand
tale told by Ann Mansker about a SINGLE study [...] is EVIDENCE that
Theo Asir
"Unique Too" <uniq...@aol.com> wrote in message
news:20030807113638...@mb-m18.aol.com...
> I found the following errors in the sites you mentioned. When a site
contains
> two items of misinformation I start to doubt the reliabilty of the rest of
> their information. Cleaning your pruners between plants isn't a bad idea,
but
> since symptoms of RMV may not show up for several years you would have to
> disinfect everytime you work on a different plant.
>
> "Mosaic:
> <snip>
> Control:
> <snip>
> Plant virus resistant roses if possible. "
> There is no such thing as an RMV resistant rose. If you graft an infected
root
> to a healthy cutting, it will be infected.
True.
I assume they meant virus free stock.
I realize this may change your cultural practice
but seriously, sterilizing between plants is good
advice for other diseases as well. most notably
crown gall.
Also this is such a grey area. When
in doubt sterilize. you can try to get tetanus
deliberately for years and not get it, but
it takes just one random infection in literally
millions of tries to kill you.
> "Rosette and Witches Broom:
> <snip>
> Control:
> The exact cause of this disease is unknown. Infected plants cannot be
cured.
> Try to control insects, particularly leaf hoppers and plant hoppers....."
>
> RRD is caused by a mite. And there is an insecticide which kills the
mites
> that spread the disease. See Ann Peck's site for more details.
> http://web.ntown.net/~apeck/index.htm
Its not 'caused' by a mite, its spread by it.
But no one knows the cause really. probably a virus.
I realize ann peck is a supposed expert
by this is truly laughable.
First the mites are too small to be seen.
So how do you know you have a
mite infestation. Usually when the
disease manifests, its too late.
Second if it is for preventing further
spread in your garden RRD is really
a rural garden disease. It comes from
elsewhere on the wind. how do you
cut off the source.
Near where I live RRD has a strong rural
presence. but Multiflora is becoming resistant
and will no doubt continue to act as a carrier.
Slash & burn is probably the only effective
method available.
Henry Kuska
at all--so
far--that Rose Mosaic Virus can spread from one plant to another in our
gardens."
Please look up the meaning of each of the words that you utilized
(particularly the "at all"). I suggest that you modify your statement to
say that there is some evidence (or even some preliminary evidence) but it
is not sufficient to convince you..
------------------------------------------------------------
You may be interested in downloading the full paper cited in:
http://www.actahort.org/books/246/246_40.htm
"Incidence of Rose Viruses in Spain", M. Cambra, J.L. Martinez-Torres, M.J.
Benaches, E. Camarasa, and M.T. Gorris, Acta Horticulturae, vol 246,pages
309-312, (1989).
They studied 4,730 rose samples. They found 4.2% of the roses had Prunus
necrotic ring spot virus. The breakdown was: 44.0 % of the minatures, 1.1 %
of the hybrid teas, and 1.5 % of Manetti rootstocks. They state: "The high
rate of PNRSV contamination in minature varieties seems to be associated to
their long existence."
Later in another paragraph they say:"....since this virus is pollen
transmitted (in addition to grafting). They later state: "The rate of
contamination in Manetti rootstock is quite low; this is probably due to the
usual nursery practice of preventing mother plants from flowering." Their
next statement is: "Manetti plants giving PNRSV positive, might have been
graft-contaminated in the most part." "
-------------------------------------------------------------
Also, does it concern you that the virus has been found in naturally
occuring wild roses?
Shiva
wrote:
>Shiva, Your statement was: "It remains a fact that we have seen no evidence
>at all--so
>far--that Rose Mosaic Virus can spread from one plant to another in our
>gardens."
>
>Please look up the meaning of each of the words that you utilized
>(particularly the "at all").
I looked it up. It is not in my dictionary. Have you got a source for
me?
>I suggest that you modify your statement to
>say that there is some evidence (or even some preliminary evidence) but it
>is not sufficient to convince you..
So you DO consider the link you furnished, in which you or Paul quote
Ann describing a single, never repeated study in which 1 to 2 % of
allegedly virus-free multiflora plants were allegedly infected via
pruners or perhaps simple *proximity* to be "evidence that rose mosaic
virus can be spread in our gardens."
I am surprised. Not only do I not consider it to be sufficient to
convince me, I do not consider it evidence at all. I imagine you must
run yourself ragged keeping up with every unreplicated study that
comes up.
>You may be interested in downloading the full paper cited in:
>http://www.actahort.org/books/246/246_40.htm
>"Incidence of Rose Viruses in Spain", M. Cambra, J.L. Martinez-Torres, M.J.
>Benaches, E. Camarasa, and M.T. Gorris, Acta Horticulturae, vol 246,pages
>309-312, (1989).
>They studied 4,730 rose samples. They found 4.2% of the roses had Prunus
>necrotic ring spot virus. The breakdown was: 44.0 % of the minatures, 1.1 %
>of the hybrid teas, and 1.5 % of Manetti rootstocks. They state: "The high
>rate of PNRSV contamination in minature varieties seems to be associated to
>their long existence."
>Later in another paragraph they say:"....since this virus is pollen
>transmitted (in addition to grafting). They later state: "The rate of
>contamination in Manetti rootstock is quite low; this is probably due to the
>usual nursery practice of preventing mother plants from flowering." Their
>next statement is: "Manetti plants giving PNRSV positive, might have been
>graft-contaminated in the most part." "
>-------------------------------------------------------------
I think not, as the above apparently does not treat rose mosaic virus.
>
>Also, does it concern you that the virus has been found in naturally
>occuring wild roses?
Tell me why it should. Please. I am trying to learn here.
Henry Kuska
--
Henry Kuska, retired
ku...@neo.rr.com
http://home.neo.rr.com/kuska/
"Shiva" <hyp...@cotse.net> wrote in message
news:058f52e12e189381...@free.teranews.com...
Shiva
Henry Kuska wrote:
http://www.realdictionary.com/E/dir/evidence.asp
Thanks, Henry, you're a peach. Here's one for you:
http://www.realdictionary.com/E/dir/evidence.asp
You know that most serious scientists would not consider a single
study by even the most reputable group to be evidence of anything, now
don't you? Of course you do.
Henry Kuska
single study by even the most reputable group to be evidence of anything,
now
don't you? Of course you do."
No, I do not. If the results of a study are not evidence, then what are
they? How can you state the above when you just gave a link for definitions
of "evidence"? Are you mixing up the concept of "accepted fact" and
"evidence"?
You may want to reexamine the following (please look for the appearance of
the word "evidence" in both links):
"The two links below address natural spread of RMV:
http://www.rdrop.com/~paul/tom_virus.html
and
http://www.goldcoastrose.org/pdf/clean-stock.pdf
This is what the U.C. Davis rose virus cleaning document states (the
goldcoastrose link above):
"The viruses that cause rose mosaic disease are most commonly spread through
propagation procedures such as budding an infected scion onto a healthy
understock, or a healthy scion to an infected understock. Disease symptoms
are not always obvious, which is why the use of virus-tested planting stock
is advantageous. There is some evidence that rose mosaic spreads in
commercial rose plantings. UC researchers are presently looking for possible
explanations.""
--
Shiva
From: "Henry Kuska" <ku...@neo.rr.com:
> Shiva said: " You know that most serious scientists would not consider a
> single study by even the most reputable group to be evidence of anything,
> now
> don't you? Of course you do."
>
> No, I do not. If the results of a study are not evidence, then what are
> they?
Silly man. You are playing semantics here, the last refuge of those
who have no rational let upon which to stand. The phrase was "evidence
that Rose Mosaic Virus may be transmitted in our gardens," for one
thing. Not just "evidence." The study you cited might just provide
evidence that the guys doing it didn't know what the hell they were
doing. In that sense, any study does indeed provide evidence--of
something, even if it is the sloppiness or stupidity of those
conducting it.
> How can you state the above when you just gave a link for definitions
> of "evidence"? Are you mixing up the concept of "accepted fact" and
> "evidence"?
I think you are using the word incorrectly, and you think I am using
the word incorrectly. The fact is, any idiot knows that the single
study you cited can not be considered "evidence that Rose Mosaic Virus
may be transmitted in our gardens." Why? Because something occuring
once may simply be a fluke. This is why real scientists look for
replication of studies, examine the scientific methods used,
investigate the use of controls and the credentials of the body that
conducted the so-called study. For you to claim to be a scientist and
yet pretend that anything you find on the Internet is a study that
provides valid evidence for the topic at hand leads me to suspect that
that you might just be one of the Rose Mosaic Alarmists I have run
into before.
Meanwhile, this hairsplitting is getting on my nerves, so I imagine
others are sick of it too.
In addition to the fact that I do not believe any single study that
has never been replicated anywhere can be considered to provide
evidence that Rose Mosaic Virus may be transmitted in our gardens, the
study you cited did not convince me.
Cass
<ku...@neo.rr.com> wrote:
I missed it. Thanks. And the information about UC's hedge trimming
experiment is discouraging as well. Then there are the reports about
heat-treated, so-called virus-cleaned, varieties showing symptons after
a number of years. Bad stuff. One wonders what percentage of garden
roses is clean!
Cass
<ku...@neo.rr.com> wrote:
> Shiva, Your statement was: "It remains a fact that we have seen no evidence
> at all--so
> far--that Rose Mosaic Virus can spread from one plant to another in our
> gardens."
>
> Please look up the meaning of each of the words that you utilized
> (particularly the "at all"). I suggest that you modify your statement to
> say that there is some evidence (or even some preliminary evidence) but it
> is not sufficient to convince you..
> ------------------------------------------------------------
> You may be interested in downloading the full paper cited in:
> http://www.actahort.org/books/246/246_40.htm
> "Incidence of Rose Viruses in Spain", M. Cambra, J.L. Martinez-Torres, M.J.
> Benaches, E. Camarasa, and M.T. Gorris, Acta Horticulturae, vol 246,pages
> 309-312, (1989).
> They studied 4,730 rose samples. They found 4.2% of the roses had Prunus
> necrotic ring spot virus. The breakdown was: 44.0 % of the minatures, 1.1 %
> of the hybrid teas, and 1.5 % of Manetti rootstocks. They state: "The high
> rate of PNRSV contamination in minature varieties seems to be associated to
> their long existence."
What does this mean, "associated with their long existence?"
Cass
<uniq...@aol.com> wrote:
> There is no such thing as an RMV resistant rose. If you graft an
> infected root to a healthy cutting, it will be infected.
I do not know that this is true at all. Rosarians have observed for
years that some virused roses are weak, sickly and damaged, while
others are vigorous, floriferous and viable. Really, there are too many
variables to know exactly what is going on, whether the really sickly
ones have RMV of both the rootstock and the scion, whether some of the
RMViruses are more virulent than others, whether the problems are
caused by rootstock incompatibility. Until testing is more accessible,
we can only speculate what is going on.
Henry Kuska
I have the actual paper, but it does not say anymore about this. I "guess"
that one or both of the following may be what they mean (the translations
that foreigh papers go through often leads to problems of this type): 1)
that the minatures were allowed to keep their flowers (i.e. they were not
pruned) so there were many opportunities for virused pollen contamination by
bees; or 2) the minatures tested were old plants that had many years
exposure to the 1 or 2 % transmission rate.
Explanation 2 was given by a European member of one of the forums as an
explanation for the high virus percentage found in old Europen rose gardens.
--
Henry Kuska
original statement is defendable in Formal English. ("It remains a fact that
we have seen no evidence at all--so far--that Rose Mosaic Virus can spread
I offered you the opportunity to revise your statement (with a suggested
revision): " I suggest that you modify your statement to say that there is
some evidence (or even some preliminary evidence) but it is not sufficient
to convince you.".
I also asked you to reference what part of the dictionary definition of
"evidence" you felt supports your use of the word (I referred you to
examples of how others were using "evidence").
I have presented the viewpoints of a number of respected scientists,
hybridizers and the Royal Botanical Garden, Sydney . Your attempt to
question (attack) my scientific judgment is disappointing; are you attacking
the scientific judgement of the above also?
Your statement: "For you to claim to be a scientist and yet pretend that
anything you find on the Internet is a study that provides valid evidence
for the topic at hand ..." deserves comment.
The above quote has a number of words but what do they collectively mean in
Formal English?
For example, you use the word "pretend":
http://www.realdictionary.com/p/dir/pretend.asp
then you use "anything"
http://www.realdictionary.com/a/dir/anything.asp
???????????????????????????????????????????
I was pleased to see that you placed the word "valid" in front of evidence -
"valid evidence" is a completely different statement than "no evidence at
all".
"Valid" is a subjective term: http://www.realdictionary.com/v/dir/valid.asp
(definition of subjective:
http://www.realdictionary.com/s/dir/subjective.asp i.e. what you consider
valid, someone else may not and vice versa.
If I am interpreting correctly what you are now stating, you are now
approaching my suggested revision to your original statement. To save
scrolling here it is again:
" I suggest that you modify your statement to say that there is some
evidence (or even some preliminary evidence) but it is not sufficient to
convince you..
Henry Kuska
My reply: yes, and in order for me to see if there is any justification to
your original statement, I need to know which meaning you are using?
Remember, you provided the link to that set of definitions for "evidence".
This is a very straight forward request.
Your continuing "habit" of reading the motive of other posters is very
interesting. I doubt that you were instructed to do that in your Formal
English studies.
Your statement:
"Until you can produce another study that even begins to suggest that RMV
can spread in our gardens, you have not produced any evidence AT ALL that
it can."
contradicts itself.
How can you use "another" (
http://www.realdictionary.com/a/dir/anothera.asp ) and then state "you have
not produced any evidence AT ALL"? In case you are unable to open the
dictionary link, here is what it says:
"another(a) - different, some other, additional
Detailed description:-
3 Dictionary Entries found
---------------------------
1) s :distinctly separate from the first
---------------------------
2) s :any of various alternatives; some other
---------------------------"
.
Henry Kuska
The third meaning was dropped. It is:
3) s :one more or an added
--
Henry Kuska, retired
ku...@neo.rr.com
http://home.neo.rr.com/kuska/
"Henry Kuska" <ku...@neo.rr.com> wrote in message
news:bDSYa.67221$ib2.16...@twister.neo.rr.com...
Unique Too
>Also, does it concern you that the virus has been found in naturally
>occuring wild roses?
I missed that one the first time around. Where is it stated RMV was found in
naturally occuring wild roses?
Julie
Unique Too
>> "Mosaic:
>> <snip>
>> Control:
>> <snip>
>> Plant virus resistant roses if possible. "
>
>
>> There is no such thing as an RMV resistant rose. If you graft an infected
>root
>> to a healthy cutting, it will be infected.
>
>True.
>I assume they meant virus free stock.
>
I didn't assume that at all. We do use the term disease resistant when
referring to either blackspot or powdery mildew so it seems logical to me they
meant there were RMV resistant roses.
>>
>> RRD is caused by a mite. And there is an insecticide which kills the
>mites
>> that spread the disease. See Ann Peck's site for more details.
>> http://web.ntown.net/~apeck/index.htm
>
>Its not 'caused' by a mite, its spread by it.
>But no one knows the cause really. probably a virus.
You're right on this one, it is SPREAD by a mite, not caused by. That was
definitly my error.
Julie
Unique Too
<cass666...@attbi.com> writes:
>> There is no such thing as an RMV resistant rose. If you graft an
>> infected root to a healthy cutting, it will be infected.
>
>I do not know that this is true at all. Rosarians have observed for
>years that some virused roses are weak, sickly and damaged, while
>others are vigorous, floriferous and viable. Really, there are too many
>variables to know exactly what is going on, whether the really sickly
>ones have RMV of both the rootstock and the scion, whether some of the
>RMViruses are more virulent than others, whether the problems are
>caused by rootstock incompatibility. Until testing is more accessible,
>we can only speculate what is going on.
Interesting. Are you saying is an RMV infected rose which remains vigoruous,
floriferous and viable "may" be RMV resistant? That is possible.
This entire RMV thread has been most informative.
Julie
MMMavocado
"The following comments are an addendum to the Virus article written by Jeri
Jennings, posted by
Tom Liggett in a discussion group as a follow-up to said article:
U.C. Davis FPMS has LONG (!!!!!) reported that "virus-free" (read that heat
treated/indexed)
plants that were grown in insect-segregated greenhouses saw the spontaneous
re-occurrence of virus
after five years. In my view, there is NO way to remove Mosaic (and mayhaps
other) virus(es) from
plants once they re infected. "
I should point out that after that statement was made, I had a flood of emails
about it, so I called up the folks at FPMS. Talked to several of them,
including Mike Cunningham, head of their rose program. I was assured,
absolutely, that no knowledgeable FPMS employee had ever said any such thing,
and that it was certainly not true, in their experience.
So, either the quote is a direct lie, or (more probably) a gross
misunderstanding of some other statement, enlarged through several generations
of gossip.
Malcolm Manners
Henry Kuska
naturally occuring wild roses?
>
Julie asked: " I missed that one the first time around. Where is it stated
RMV was found in naturally occuring wild roses?"
First, to avoid confusion among the readers of this thread, this quote is
not from my original link. In that link the statements that I provided are
the following two:
1) "In a 1962 American Rose Annual article the following is stated: "L.C.
Cochran found two roses in California naturally infected with the virus of
peach ring spot." (Peach ring spot is another name for PNRSV, the main
component of RMV in the U.S.).
---------------------------------------------------------------------------
-----------------------------------------------
2) "AND for other rose viruses there are papers that have found "non Rose
Rosette Disease virus" - (RRD is a story in itself, it also started with
"research" stating that it would not spread) in other naturally occurring
wild roses in the U.S., and seed transmission and nematode transmission in
other countries."
----------------------------------------------------------------------------
------------------------------------------------
The following is a two part expansion of some of what is behind the concise
statements in my link (I kept the information in the link focused on PNRSV,
the main component of what collectively is called RSV):
Part 1) Dr. L C. Cochran's 1972 American Rose Annual article: "VIRUSES
INFECTING ROSES"
Approximately nine separate virus diseases affecting roses have been
recorded. The one most commonly occurring on roses has been loosely
described under such names as: typical mosaic, yellow mosaic, streak, rose
viruses 1, 2, & 3, vein banding, line pattern, chlorotic mottle, prunus
ringspot, etc. Research data delimitating this group is still incomplete and
until completed will be referred to under the name rose mosaic.
Other viruses which have been used to infect roses or have been recovered
from naturally infected plants include: (1) Tomato ringspot virus,
transmitted by the nematode Xiphinema americanum, occurring sporadically in
western United States; (2) Streak, vector unknown, occurring sporadically
but latent in some cultivars; (3) Arabis mosaic virus, common in roses in
Europe, transmitted by the nematode X. diversicaudatum; (4) Strawberry
latent ringspot virus transmitted by the same nematode; (5) Apple mosaic
virus reported from Europe and Australia; (6) Tobacco ringspot virus,
reported from Iowa; (7) Witches' broom virus, reported from Nebraska and
California; (8) Rose wilt virus, reported from Australia and a new disease
occurring in California, resembling rose wilt, which causes a disease
tentatively called spring dwarf. Without doubt a careful study might reveal
some other viruses, such as Tobacco mosaic and tobacco necrosis in rose."
Note the use of: "or have been recovered from naturally infected plants" and
statements such as:
"Tomato ringspot virus, transmitted by the nematode Xiphinema americanum,
occurring sporadically in western United States".
Also note, although he numbers the statements as if the references are
provided, the references were not given.
AND
Part 2) The published paper by R. H. Converse and A. B. Bartlett, Plant
Disease Reporter, volumn 63, pages 441-444, (1979). They studied 21 wild
rose plants from 17 Oregon, U.S.A. locations. 5 plants out of the 20 that
were tested by agar-gel diffusion (1 plant was not tested) were found to
have tobacco streak virus ( see:
http://image.fs.uidaho.edu/vide/descr811.htm ). The positive testing plants
came from 4 of the 17 sites (2 positive out of 2 tested from one site; 1 out
of 1 tested from another site; 1 out of 3 from another; and 1 out of 1 from
another).
----------------------------------------------------------------------------
----
To minimize scrolling I have reproduced the literature introduction to my
original link (which defines what viruses are considered part of what is
being discussed in the scientific world). The word "ilarvius" for our
purpose can be thought of as just a more fancy way of saying "virus".
Title: Roses: virus and virus-like diseases.
Author: Lisa-V
Published in: Colture-Protette. 1998, 27: 5 Supplement, 35-38; 14 ref.
Language of article: Italian
Abstract: "Notes are given on the viruses and virus-like diseases that are
known to affect roses around the world. The most common and widespread virus
disease is rose mosaic, associated especially with prunus necrotic ringspot
ilarvirus (PNRSV), apple mosaic ilarvirus (ApMV), arabis mosaic nepovirus
(ArMV) and strawberry latent ringspot nepovirus (SLRV), but also with
tobacco ringspot nepovirus, tobacco streak ilarvius and tomato ringspot
nepovirus. Tobacco mosaic tobamovirus and an unidentified closterovirus are
found sporadically. The virus-like diseases of unknown aetiology include
rose ring pattern, rose flower break, rose streak, rose rosette (or rose
witches' broom), rose leaf curl, rose spring dwarf and rose wilt. Other
disorders are caused by hormonal imbalances or other types of
incompatibility between the graft and the rootstock of unknown aetiology,
such as rose bud proliferation, rose dieback (or rose stunt) and frisure.
Techniques for diagnosing viruses in roses and methods for their control are
described." (The actual articles are copyrighted. This is why one will only
see the abstract on public forums.)
Henry Kuska, retired
ku...@neo.rr.com
http://home.neo.rr.com/kuska/
"Unique Too" <uniq...@aol.com> wrote in message
news:20030808170027...@mb-m12.aol.com...
Henry Kuska
Mediterranean Plant Protection Organization which covers rose virus
certification, see:
Cass
Kuska <ku...@neo.rr.com> wrote:
Thanks for all the information. Have you considered an article in the
American Rose Annual? There is never enough content in ARS pubs for my
tastes.
Henry Kuska
American Rose Annual: I assume that the U. Calif. Davis research is nearing
completion. I hope that they would then write such an article as they are
the "horse's mouth".
I "expect" that they are preparing something for the conference covering
virus diseases of ornamental plants which is scheduled for 2004. (Often,
researchers try to present their results at conferences such as this one in
order to assure that the work gets maximum exposure among those working in
the field.)
. March 9-13, 2004, Taichung (Taiwan): XI International Symposium on Virus
Diseases of Ornamental Plants. Info: Dr. Chin-An Chang, Taiwan Agricultural
Research Institute (TARI), 189 Chung-Cheng Road, Wufeng, Taichung 413,
Taiwan. Phone: (886)423302803, Fax: (886)423331089, email:
cac...@wufeng.tari.gov.tw or Dr. Anne Marie van Zaaijen, Duinroos 35, 2202
DB Noordwijk, Netherlands. Phone: (31)71-3618182, Fax: (31)71-3617591,
email: a.van...@inter.nl.net web:
http://www.tari.gov.tw/isvdop-11/index.html
See:
http://www.ishs.org/calendar/index.htm
Cass
> Cass, concerning your suggestion to publish an article on the subject in the
> American Rose Annual: I assume that the U. Calif. Davis research is nearing
> completion. I hope that they would then write such an article as they are
> the "horse's mouth".
Henry, I can appreciate your reluctance to survey the literature when
such a report is expected shortly. However, the amount of accurate
information in a form readily accesssible to even well-informed
rosarians is quite limited. I would view a survey as a precursor to the
Davis report, which undoubtedly will include several provisos that
"more research is needed." That is the perpetual state of knowledge.
Additionally, there is an unsatisfying air of "Don't worry, be happy"
surrounding the occurrence of rose mosaic virus. Don't we all wonder if
we would need fewer fungicides and in certain parts of the country
suffer fewer winter losses if there were fewer virused plants foisted
on on the public? I was delighted this spring to see Jackson Perkins
offering guaranteed virus free plants....for close to $20 each.
> I "expect" that they are preparing something for the conference covering
> virus diseases of ornamental plants which is scheduled for 2004. (Often,
> researchers try to present their results at conferences such as this one in
> order to assure that the work gets maximum exposure among those working in
> the field.)
Looking at this list of mosaic viri (see? kits are available)
http://www.dsmz.de/plvirus/elisa_o.pdf, it is no surprise that roses
suffer from mosaic virus. I've seen common weeds in my yard suddenly
show up with mosaic or variagation of the foliage.
I suspect that the 1 to 4 % contagion rate is low. My experience with
both budded new releases and with old roses is not reassuring, more on
the order of 25% than 1 %. That experience has bolstered my interest in
collecting and propagating own root, healthy old roses from very old
homes. I read your information about mosaic symptoms showing up as
early as the 1860's. Whatever its rate of transmission then, it could
only increase with modern transportation and production techniques.
Apart from different rates of contagion for different virii, it seems
obvious that different modes of transmission would have different rates
of success. Add that to different susceptibility of cultivars, and the
landscape gets complicated quickly. But "Don't worry be happy" seems
just simple minded and an abandonment of efforts to improve.
Transmission by pruning equipment is the most obvious concern of most
home gardeners. Not knowing (a) how easily transmissible the viruses
are and (b) how many roses suffer from them without showing symptoms,
may make all efforts futile. There is no way of assuring the
cleanliness of pruners even after washing, dipping and drying,
especially with little more more than strings of protein involved. That
doesn't mean I will abandon those efforts. Disposable pruners? No
pruning? Not likely.
Just my thoughts after reviewing your materials.
Henry Kuska
have been busy being "grandpa", but I did have time during their naps
to search for literature evidence that related to what Tom Liggett
said about rose virus returning to heat treated roses. The first
thing is the following link
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&safe=off&threadm=1998071903395300.XAA24101%40ladder01.news.aol.com&rnum=2&prev=/groups%3Fq%3D%2522kitty%2Bbelendez%2522%2Bvirus%26hl%3Den%26lr%3D%26ie%3DUTF-8%26safe%3Doff%26selm%3D1998071903395300.XAA24101%2540ladder01.news.aol.com%26rnum%3D2
That link states that it was stated at a meeting and that others heard
it also.
-------------------------------------------------------------------------------------------
The reference that appears to be the most interesting is:
Title: Recent Issues raised in the Evaluation of Virus Removal and
Inactivation
Authors: White, E.M., and Woodward, R.S.,
Published in Genetic Engineering News, volumn 15, page 6, (1995).
(Note, the page number is ambigious in the source that I found this
in.)
Unfortunately no abstract was given. Can anyone provide look this
reference up?
--------------------------------------------------------------------------------------------------
A number of German papers (by the same labatory plus other laboratory
co-authors) appear to say something which is related to this issue.
I purchased one of the most recent of their papers.
Title: Phytosanitary Improvement of Fruit Tree Species: Diagnostic
Strategies in Virus-Indexing of In Vitro Plants
Authors: A. da Camara Machado, D. MendonCa, M.S. Lopes, E. Knapp, V.
Hanzer, W. Arthofer, H. Katinger, M. Laimer da Camara Machado
Authors affiliation: this was a combined publication from a
laboratory in Portugal and a laboratory in Austria.
Published in: Acta Hort., volumn 472, pages 511-516, (1998).
In the actual paper they say that one of the points of the
investigation was: "2) Are virus elimination treatments merely
reducing the virus titer, but are they failing to eliminate some
viruses entirely. If so, how long does it take for those viruses to
reaccumulate to detectable levels?"
The above sounds like exactly what we are looking for (but not on
roses). In in their Results section, they say:
"Furthermore, we tried to understand whether, in some cases, virus
elimination treatments merely reduced the virus titer or failed to
eliminate some viruses entirely. If so, how long does it take for
those viruses to reaccumulate to detectable levels? Depending on this
situation, how many tests are necessary to confirm initial negative
test results? It is known that elimination treatments may depress the
pathogen titer below the threshold level of detection (Fridlund,
1989). In this respect the effects of thermotherapy on the titer of
ASGV and ACLSV were investigated in in-vitro-shoots of several apple
cultivars. Irrespective of the duration of thermotherapy treatment
(depending on heat sensitivity of the plant material), the virus titer
of both ASGV and ACLSV initially was decreased dramatically. Shoots
that were multiplied in vitro for over 2 years and used as starting
material. Before undergoing thermotherapy, they tested 100 % positive
for ACLSV, 100 % negative for ApMV and showed values around the
threshold level of 36% for ASGV, as shown in Fig. 1 for the Austrian
cultivar Maschanzker.
After thermotherapy meristems were excised and regenerating shoots
submitted to a multiplication step to increase the number of shoots.
After 7 months, plantlets were tested again and showed mainly negative
values or vahies around the threshold for ApMVand ACLSV, indicating
that the elimination success was satisfactory. On the other hand,
after 7 months 7% of the samples were postive when tested for ASGV,
indicating a different reaction pattern (Fig.
1)......................................
It is a definite fact that plants with a double infection of ASGV and
ACLSV are more difficult to- treat. However, we do not know, so far,
on which mechanism this synergistic effect may rely. Samples of the
different groups were compared (Fig. 2). From the nontreated positive
control plants, only ApMV was not detected after this period in vitro.
Values around the threshold were obtained from the originally negative
plantlets. In other cultivars, from originally negative clones
multiplied in vitro, a high number of samples showed ASGV positive
results after more than one year of in vitro culture.
-------------------------------------
The detection of ASGV by ITP in shoot tips from several potted plants
of Maschanzker grown for 2 years in the greenhouse (data not shown)
was, however, a concern. Therefore, the need for a more reliable
detection system seems evident."
The DISCUSSION section contained the following:
"As it is still common practice in sanitation programs to carry out
in-vitro treatment and ex-vitro re-testing for selection of plant
material. The result is a lack of knowledge of the speed of recovery
of low pathogen levels under in-vitro conditions (IPGRI/FAO,
1994)..........................
Elimination treatments depressed virus titer, as could be shown for a
wide range of cultivars. Thermotherapy, however, alters or destroys
viral proteins, therefore, serodiagnostics are of little value for
reliable early screening. Furthermore, there remain the limitations of
current ELISA-based serological tests which might be not sensitive
enough to detect very low levels of virus. Also, the time required by
the different viruses to recover up to a level of detection from low
levels of infection will again be dependent on the pathogenhost
combination. ACLSV was readily detected after re-accumulation above
the threshold level whereas the well-known problems in reliable
diagnosis of ASGV were further encountered even after several tests of
in-vitro cultures (Fuchs et at, 1988, Gilles and Verhoyen, 1992). We
assume that molecular diagnostics will improve the aforementioned
problems. Other methods which, so far, are not used for routine
diagnostics, like PCR or immuno-capture-PCR, will be introduced into
the sanitation program to improve the system of diagnosis for in-vitro
plants."
-----------------------------------------------------------------------------------------------------------
There were several Japanese papers which also appeared to be related
to our topic. The following is one:
Title: Evaluation of virus-free bulblet production by antiviral and or
heat treatment in in vitro scale cultures of Lilium longiflorum
'Georgia' and L-X 'Casablanca'
Authors: Xu PS, Niimi Y
Authors affiliation: Xu PS, Niigata Univ, Fac Agr, Ikarashi 2-8050,
Niigata 9502181, Japan
Published in: JOURNAL OF THE JAPANESE SOCIETY FOR HORTICULTURAL
SCIENCE, volumn 68, pages 640-647, (1999)
Abstract: "This study evaluated the effects of chemotherapy (addition
of ribavirin or 2-thiouracil to a medium) and/or heat treatment at 35
degrees C on the Production of virus-free bulblets in the scales
culture of Lilium longtiflorum 'Georgia' and L. x'Casablanca',
infected with lily symptomless virus (LSV), tulip breaking virus-lily
(TBV-L), and cucumber mosaic virus (CMV).
1. When scales were cultured on a medium with ribavirin at 50 mu M,
ELISA-absorbance values at 405 nm for LSV in the incubated scales
decreased as the incubation Lime lengthened, whereas the TBV-L, values
of the scales decreased at almost the same rate as those of the
control.
2. When scales of L. longiflorum 'Georgia' were cultured on medium
with antiviral chemicals, the number of bulblets formed decreased as
concentrations of antiviral chemicals increased. Viruses were detected
in about 20% of the bulblets at the end of culture when the scales
were cultured on medium with ribavirin and 2thiouracil at 50 mu M;
however, more: than 44% of the bulblets, which were transplanted into
soil and cultivated in the greenhouse for 6 months, showed the
positive reaction in viruses.
3. Scales excised from bulblets heat-treated at 35 degrees C for 4
weeks formed fewer bulblets than those of control, especially the
scales of 'Georgia'.
4. Chemotherapy in combination with thermotherapy was more effective
in decreasing the number of virusinfected bulblets than was the single
treatment. When scales, kept at 35 degrees C for 4 weeks, were
cultured on medium with 5 mu M ribavirin, viruses were detected in 30%
of the bulblets of 'Georgia' and 6% of those in 'Casablanca' at the
end of in vitro culture. However, viruses were detected in 100% of the
bulblets in 'Georgia' and 44% of those in 'Casablanca' which were
transplanted into sail and cultivated in the greenhouse for 6 months."
The Ohio State Research Laboratory at Wooster does subscribe to this
journal. However, the article is written in Japanese so I cannot add
to the abstract.
----------------------------------------------------------------------------------------------
My comment (Henry Kuska): it appears that, at least in some plant
systems, treated material may have a virus level below the detection
limit of ELISA, and that small amount of undetected virus may then
grow to detectable levels.
------------------------------------------------------------------------------------------------
.
The following is a paper which compares ELISA detection of PNRSV to
other methods:
Title: Comparative analysis of ELISA, nonradioactive molecular
hybridization and PCR for the detection of prunus necrotic ringspot
virus in herbaceous and Prunus hosts
Authors: Sanchez-Navarro, Apancio, Rowhani & Pallas
Published in: Plant Pathology, volumn 47, page 780, (1998).
Abstract: "Comparative analysis of ELISA, nonradioactive molecular
hybridization and PCR for the detection of prunus necrotic ringspot
virus in herbaceous and Prunus hosts
Three methods were compared for the detection of prunus necrotic
ringspot virus in herbaceous and woody plants: DAS-ELISA, nonisotopic
dot-blot hybridization and reverse transcriptional polymerase chain
reaction (RT-PCR). When purified virus preparations were used, the
detection limit of the RT-PCR technique was 1.28 pg mL-1 whereas
nonisotopic molecular hybridization and DAS-ELISA allowed detection of
0.8 ng mL-1 and 4 ng mL-1, respectively. Several sample processing
procedures were evaluated for virus detection by the nonisotopic
molecular hybridization technique. When a very short and simple sample
processing method was used, the detection limit of the nonisotopic
molecular hybridization technique was 25 times higher than that of
DAS-ELISA and 625 times lower than that of RT-PCR. A comparison of the
level of virus accumulation in mature fruits and in leaf tissue showed
that, on average, 125 times more virus was found in the fruits."