Re: [OGD] Virus and orchid pollen
At 07:41 AM 7/26/2008 +1000, you wrote: >HI all >Want to do some breeding with some older rare Laelia anceps varieties, but >feel one of them is virused > >Does any one have an opinion on the transmission of virus through pollen? > >Kind Regards, > >Wayne Turville >Australian Orchid Nursery This one article seems to indicate that it is possible: http://members.optushome.com.au/bdobson/Virus%20in%20Orchids.html ---Prem Prem Subrahmanyam curator, www.flnativeorchids.com The Florida Native Orchids Website ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus and orchid pollen
HI all Want to do some breeding with some older rare Laelia anceps varieties, but feel one of them is virused Does any one have an opinion on the transmission of virus through pollen? Kind Regards, Wayne Turville Australian Orchid Nursery Ph: (03) 5977-3122 Fax: (03) 5977-3350 Email: [EMAIL PROTECTED] Web: www.australianorchids.com.au www.cymbidium.com.au ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus Transmission
And if there are exposed lesions, those fluids are not available? Ray Barkalow - First Rays Orchids - www.firstrays.com Plants, Supplies. Books, Artwork, and lots of Free Info! - Original Message - From: <[EMAIL PROTECTED]> To: Sent: Sunday, March 16, 2008 9:09 AM Subject: Re: [OGD] Virus Transmission > In a message dated 3/16/08 12:15:38 AM, Ray writes: >> Did you forget water splashing from one plant to another? >> > That is a common way of transmitting bacterial infection, not viruses. > Remember the rules you read all the time about AIDS; the same principles > apply. > Orchid viruses are spread by the transmission of "body fluids": unsanitary > cutting, sloppy repotting, unwashed hands & tables, and group potting. And > of course, > sex. I have lost a couple of seed parents to infected pollen parents. > Iris > > > > ** > It's Tax Time! Get tips, forms, and advice on AOL Money & > Finance. > (http://money.aol.com/tax?NCID=aolprf000301) > ___ > the OrchidGuide Digest (OGD) > orchids@orchidguide.com > http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus Transmission
In a message dated 3/16/08 12:15:38 AM, Ray writes: > Did you forget water splashing from one plant to another? > That is a common way of transmitting bacterial infection, not viruses. Remember the rules you read all the time about AIDS; the same principles apply. Orchid viruses are spread by the transmission of "body fluids": unsanitary cutting, sloppy repotting, unwashed hands & tables, and group potting. And of course, sex. I have lost a couple of seed parents to infected pollen parents. Iris ** It's Tax Time! Get tips, forms, and advice on AOL Money & Finance. (http://money.aol.com/tax?NCID=aolprf000301) ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus Transmission.
In a message dated 3/16/08 12:15:38 AM, [EMAIL PROTECTED] writes: > Did you forget water splashing from one plant to another? > ** It's Tax Time! Get tips, forms, and advice on AOL Money & Finance. (http://money.aol.com/tax?NCID=aolprf000301) ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus and wood benches
Giles, your the second one to mention this to me. I was discussing viral problems with James Rose, and that is exactly what he was concerned about. Next time I am at Cal Orchids, I'll ask if he has come up with a treatment for the benches. Personally, I don't have this problem as I grow on hardware cloth and for some reason, it is rare for roots to leave my pots. It may be because I use round pots that don't have holes at the lower exterior edges, so when the roots hit the bottom, they generally wind round and round inside the pot without finding the holes. If I do see a root leaving the pot, I pull and replace the root ball, which repositions the root inside the pot. Any attachment to a surface that is questionable requires that the root be cut, but I think that the virus may be transferable during the attachment time, don't know for sure, but my greenhouse is dry enough that I can't ever remember a root attaching to the wood supporting the hardware cloth. One of the benefits of living in dry Arizona I suppose. One of the interesting things noted by Mr. Rose was that the incidence of virused offspring using green pod culture with a virused pod parent was very low. This was interesting, because green pod culture appears to be the norm, and I am depending on seedlings to be generally free of virus, which would not be the case if green pod culture had a high incidence of transferring virus to the seedlings. On a side note, I use a mix of 2 parts small perlite to 1 part Canadian peat. I recently corrected the PH to a mid 6 by the addition of oyster shell. After about 6 months in this mix, I have a flurry of roots leaving the tops of pots, and a few other indications by a number of plants of some objection to this mix. Am now going mostly back to the highly acidic mix, with a little gypsum added to counteract the fluorine in the perlite, that seemed to be the preference of most. Cynthia, Prescott, AZ -- From: "giles" <[EMAIL PROTECTED]> The recent discussion about virus infection raises an issue I have long wondered about. If I find some infected plants in my greenhouse I can move those plants out of the greenhouse, but isn't there some danger of the bench surfaces retaining some latent virus that could then infect new plants? Orchid roots have a habit of growing through the bottom of pots and adhering to bench surface, and then being torn open when the pot is moved. If that plant was infected, could the infection spread from that bit of root on the bench to a new plant sitting on that same spot? And how does one sterilize the surface of a bench, especially one made of wood? Any comments or suggestions would be much appreciated. Giles Smith Santa Monica, Ca. ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus
Hallo Icones, I would appreciate receiving a copy of the virus cleaning article. Wishing you all the best for the coming year, Jean De Witte ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus
The recent discussion about virus infection raises an issue I have long wondered about. If I find some infected plants in my greenhouse I can move those plants out of the greenhouse, but isn't there some danger of the bench surfaces retaining some latent virus that could then infect new plants? Orchid roots have a habit of growing through the bottom of pots and adhering to bench surface, and then being torn open when the pot is moved. If that plant was infected, could the infection spread from that bit of root on the bench to a new plant sitting on that same spot? And how does one sterilize the surface of a bench, especially one made of wood? Any comments or suggestions would be much appreciated. Giles Smith Santa Monica, Ca. ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus
Hi Roger. Critter Creek Labs tests for CMV and ORSV independently, their double well test actually being a 4 well test, 2 each, so they can report the incidence of each in the sample. Yes, it is pricy, and they raised their prices last year, after my last testing. There is a price break at 10 samples, and again at 21, so in quantity, it is $5.25 per sample. Not only is it prohibitive for testing my entire greenhouse of 1000 plants, but it only tests for these 2 viruses, with about double the cost if you include their Bean Yellow Mosaic (BYMV) test. While the other viruses are uncommon, it does not mean your collection will be without them if it is large and diverse enough. The light microscope/inclusion body test should be capable of picking up all viruses, but there are several different dyes and processes to cover the various types. All testing has its percentage of failures, and by testing myself, I should be able to revisit certain plants as continuing symptoms suggest a possible missed infection. Icones, I would like a copy of the Applied Biology article, but will check with our Jr. College Library after the holidays. They have been able to get reprints for me before, and I expect this would not be an exception. ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus
I though some of you might be interested to know that in 1993 Lim, Wong and Goh published, in the Annals of Applied Biology, a process to clean orchid plants of virus. It was successful. If anyone does not have access to this journal send me a request off line and I will send you a copy. icones ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus
Hi Cynthia-- Does the testing service actually identify the particular bacteria or or virus? I suppose that could get pretty costly but it sure would be interested to see something more focused on actually specific bugs. Regards/Roger, in Bangkok On 12/21/07, Schnitz <[EMAIL PROTECTED]> wrote: > > There is a process, maybe used in Australia too, that cures grape vine > cuttings of virus by immersing in hot water for a number of minutes. I > tried this process on some of the first plants to come back with a positive > test. All leaves were lost, and most plants did not recover, but I am > convinced the percentage of recovery could be greatly improved with the use > of some really good systemic fungicides. The few that did grow on to be > very small starts had very bad leaf and bulb spotting that was obviously a > continuation of the virus. > > Just getting the virused plants out of the greenhouse is a comfort, as I > am concerned about something as simple as bumping a green root tip against a > wall or bench top, and having the wounded root pick up something from > greenhouse surfaces. I am not worrying about the plants just sitting next > to each other, as it does take an open wound to allow transmission. > > Cynthia > ... ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus
There is a process, maybe used in Australia too, that cures grape vine cuttings of virus by immersing in hot water for a number of minutes. I tried this process on some of the first plants to come back with a positive test. All leaves were lost, and most plants did not recover, but I am convinced the percentage of recovery could be greatly improved with the use of some really good systemic fungicides. The few that did grow on to be very small starts had very bad leaf and bulb spotting that was obviously a continuation of the virus. Just getting the virused plants out of the greenhouse is a comfort, as I am concerned about something as simple as bumping a green root tip against a wall or bench top, and having the wounded root pick up something from greenhouse surfaces. I am not worrying about the plants just sitting next to each other, as it does take an open wound to allow transmission. Cynthia "Interesting. Of course, knowing that the plant is infected does not take one much further forward, unless you throw it out. I recall some Australian experiments (on crop plants) which showed that in common with the sort of virus that you or I encounter, high temperatures upset the ability of the virus to reproduce. They put infected plants in chambers with light, 100% humidity and a temperature around 55C for a couple of weeks, from which they emerged pale, thin and virus free. I suspect orchids would emerge virus free because they, like the viruses, were dead." Oliver Sparrow +44 (0)1628 823187 www.chforum.org ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus testing
SCHNITZ Quote: >Hi Oliver. All testing so far has been with Critter Creek Labs. Interesting. Of course, knowing that the plant is infected does not take one much further forward, unless you throw it out. I recall some Australian experiments (on crop plants) which showed that in common with the sort of virus that you or I encounter, high temperatures upset the ability of the virus to reproduce. They put infected plants in chambers with light, 100% humidity and a temperature around 55C for a couple of weeks, from which they emerged pale, thin and virus free. I suspect orchids would emerge virus free because they, like the viruses, were dead. Actually, very little is known about plant immune systems. They have them: assorted agglutination compounds analogous to antibodies which gum up the works, and more active systems which use short-chain RNAs to 'silence' genes on the virus genome, or to shut down part of the plant's biochemistry on which the virus depends. These get triggered by e.g. jasmonic acid, ethylene and related messages but they are not at all understood. I have no idea whether there is a documented example of a plant "throwing off" a virus infection. __ Oliver Sparrow +44 (0)1628 823187 www.chforum.org ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus testing
Hi Oliver. All testing so far has been with Critter Creek Labs. I, and sometimes with another person's samples added, started with the cheaper greenhouse screening, only to discover some obvious false negatives, so at some point, we changed over to the double well test. I retested some that I hoped would have been false positives, but no luck, they were still positive. Some statistics: 261 tests made on 234 different plants for CMV and ORSV, and another 10 for BYMV for some oddly acting plants just to see if this was something to be concerned about. Approximately 1/3 of the plants tested positive for one or more of the common viruses, but none for BYMV. The incidence was much higher for plants in my collection for a long time, and lower, but still substantial, for recently purchased plants All four Vanilla plants, 2 planifolia, a pompona, and an unknown Mex. species, were positive for CMV, and the thin fast growing planifolia that I thought was a seedling, was also positive for ORSV. Of 14 reedstemmed Epis I brought with me from California 5 years ago, 1, an Epicatt, was negative, 7 were positive for both CMV and ORSV, 4 for ORSV only, and 2 for CMV only. But 2 of the ones listed as having both, had a second test (a different division of each) that tested positive only for CMV. ORSV may be an iffy test. One of the CMV plants was Epiphronitis Veitchii. I had an opportunity to test a couple of other clones of this hybrid (one of which may have been a long separated division of the same plant as mine), and both tested positive for CMV. Of the Reedstemmed plants purchased more recently, about half tested positive with results similar to the above. I have not tested anything in the last year, and hope to do my own testing in the future with a high power light microscope looking for viral inclusion bodies. I have all the equipment, the chemicals, the test plants (I am maintaining most of the virused plants in a bay window in my home), but not the time to delve into this new and very complex process. If anyone would like to look into this technique, you can look at the Oct '86 AOS bulletin, or check out this site: http://plantpath.ifas.ufl.edu/pdc/Inclusionpage/Howto.html But trust me, in this day and age, the chemicals are NOT easy to come by. The companies that sell them will not ship to a home address, only a business. And I am sure a very good microscope would be needed, as well as info from both of the sources above. Expect to spend a thousand for the microscope, and another for the chemicals and supplies. Cynthia, Prescott, AZ 9Date: Tue, 18 Dec 2007 12:26:53 + From: Oliver Sparrow <[EMAIL PROTECTED]> Subject: Re: [OGD] virus testing To: orchids@orchidguide.com Message-ID: <[EMAIL PROTECTED]> Content-Type: text/plain; charset=us-ascii Quote: "Schnitz" <[EMAIL PROTECTED]> >I will point out my recent observations re:virus and Vanilla. The last 4 Vanilla plants I bought tested positive for virus I would be interested to know which virus, and how you tested for it. (A single cubic centimetre of 'clean' water has around a billion virons in it, after all.) __ Oliver Sparrow +44 (0)1628 823187 www.chforum.org ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] virus testing
Quote: "Schnitz" <[EMAIL PROTECTED]> >I will point out my recent observations re:virus and Vanilla. The last 4 >Vanilla plants I bought tested positive for virus I would be interested to know which virus, and how you tested for it. (A single cubic centimetre of 'clean' water has around a billion virons in it, after all.) __ Oliver Sparrow +44 (0)1628 823187 www.chforum.org ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus warning
Oliver reported > The sender's ID suggests that this comes from off this list. Others will, therefore be likely to receive it. This has been raised many times. The "From" field does not necessarily indicate the sender of the virus. The way most viruses (or more correctly, worms) work these days is that they spoof the sender's email address by picking any address that it can locate on the infected PC. But yes, there is a good chance that someone on this list is infected so it's wise to invest in good quality antivirus software and keep it up to date. Cheers...Steve ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus warning
I received a virus (captured, expunged) in an e-mail headed thus: To: "Director" <[EMAIL PROTECTED]> Subject: Francis From: "Rfs" <[EMAIL PROTECTED]> Date: Mon, 11 Sep 2006 16:32:34 -0600 The sender's ID suggests that this comes from off this list. Others will, therefore be likely to receive it. __ Oliver Sparrow +44 (0)20 7736 9716 www.chforum.org ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus
Hello, someone told me that it is impossible for Bulbophyllum to have virus, is this true? Thank you and many greetings, Marianne . ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus
I have been monitoring the thread on Virus but have not had time to contribute. In 1986, I bought the remains of the Shaffer Phalaenopsis stud bench. At that time people were becoming increasingly aware of virus in older collections. I wanted to test all of the breeding stock so I would not be vectoring virus when I was making crosses. At that time only anti-sera available were for CyMV and OSRV. Out of about 140 tests, I got a little over 50 positives for CyMV, and about 25 for OSRV. I cannot speak to the issue of false positives, as I had no way to verify the results of the serological tests. What I needed to do was figure out a way to use these plants for breeding, without further spreading the virus. Some people were advocating yearly testing, but for a large number of plants, this was prohibitively expensive, and would not guarantee that you do not transmit virus. The plan I came up with was essentially this: - Assume all plants have virus, - put pollen ONLY on backup copies of plants, (yes, I made LOTS of stem propagations), - dry sow all seed unless cross is such low fertility that green-capping was the only way to get seed, - control potential insect vectors, - of course, use sterile tools when repotting or removing old flower spikes, etc. This plan got me out from under continual testing. It ensured that I would not be transmitting any additional virus to my original stock plants. Twenty years later, I am still using the same plan. I have a large number of "heirloom" Phalaenopsis in my collection, many of which were virused when I checked them twenty years ago. I would like to comment on one thing about a false sense of security. There are a huge number of virii that could potentially infect orchids, most of which have no anti-sera available for testing. So, an anti-serum test showing no sign of CyMV or ORSV doesn't mean that your plants is not infected with BYMV or something else. It is much safer to assume that all plants are virused with something as yet unknown. This is not to say that there is no benefit to testing, but that a plant that tests clean for CyMV and ORSV may still be infected with something else. Just my two cents based on my experience. rob't Robert Bedard http://www.robert-bedard.com/orchids/ ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus pictures updated.
I have updated my 'Virus in Orchids' pbase site and included the type of virus. http://www.pbase.com/schnitz/virus_in_orchids I notice that I don't have any leaf pictures for ORSV only. CMV apears to occur about 4 times as often in singly infected plants. I will look over the remaining virused plants when I have time to see if there are any good symptoms in ORSV infected plants to take pictures of. I am beginning to suspect that the ORSV data is not a reliable as the CMV data. Cynthia, Prescott, AZ ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus in orchids
On the questions about virus: I have been virus testing. I have a few pictures of the virus symptoms on my pbase site. http://www.pbase.com/schnitz/virus_in_orchids There is no guarantee that the symptoms seen there are any kind of surefire indication of virus, or are even related at all to the virus. Just pictures of how the plant looked around the time the plant tested positive to virus. This site will be updated in a couple of weeks with a few more pictures. Some of my observations are: Paphs do get virus. Two out of the three Paphs tested were positive for CMV. These were around for many years. Of 200+ tests so far for CMV and ORSV, about a 1/3 of the plants were positive for virus. Probably is high because the worst plants were tested first. Cattleyas get both CMV and ORSV, as do Laelias, Epidendrums, and others related. Many recently purchased plants from big time orchid nurseries were virused. The responses from the nurseries were mixed. Some virused plants showed no symptoms. Some plants that looked bad, tested negatively to CMV and ORSV. It is still possible that other viruses are present. If someone could direct me to a lab that tests for viruses other than CMV, ORSV, and BYMV, I would appreciate the lead. A variety of the worst looking non-pleurothalid plants, but negatively testing for CMV and ORSV, were sent for BYMV testing, and all came back negative. I have had two false negative results with green house screening, and now use the Double Well tests (Critter Creek). Since the removal of all these poorly growing plants, growing orchids is fun again. Cynthia, Prescott, AZ >> Recently, on a different forum, a person showed pictures of orchids he >> suspected of harboring >> virus. Of course no one can tell from a picture whether a plant is >> virused or not.It should be >> tested.I was about to recommend to the person showing the pictures that >> he get his plants >> tested when I realizedthat I wouldn't know what the test results would >> mean.Anyone interested >> in talking about viruses? >> >> I wondered about how we judge 'by sight' if a plant has a virus.I know >> about color break in a >> bloom.I know about a trapeziodal mark on a leaf of a cymbidium.I know >> about longitudinal >> streaks in a leaf. >> >> Of these 3 the only one I believe to be pathognomonic is the trapezoidal >> mark on a cymbidium >> leaf. Color break can come from a variety of sources, heat, pesticides >> are two that come to >> mind. Streaked leaves from heat or other poor culture. >> >> In the back of my mind I recall that old cut-flower houses didn't really >> care about virused plants >> as long as the virus didn't affect the bloom,therefore thereare several >> viruses >> housedinorchids, but since they don't affect the blooms they aren't >> considered a problem. Also >> in the back of my mind I recall that labs only test for a few viruses and >> you have to know which is >> virus a problem for your plant; like should you care aboutodont ring spot >> or cymbidium virus if >> you only grow cattleyas? Which brings up another possible myth: not all >> orchids are 'susceptible' >> to virus (Paphs aren't?? something like that.) >> >> Any information would be a help. Obviously I've got a lot to learn >> >> K Barrett >> N Calif, USA ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus testing lab
I am currently using Critter Creek Lab in Lincoln, CA. There web site has info on the tests they do. Mostly I use the green house screening, but with plants whose look disagrees with the result, or the loss is too painful, I have the plant retested with their 4 well test. One false negative (a plant with color break in the flowers) was cleared up with the further test, and a plant with no symptoms at all still came up positive on the more elaborate test. I think one should avoid any sample material that is desiccated or more than 2 years old. http://crittercreeklab.s5.com/ Cynthia, Prescott, AZ "What is the testing that is being done to identify them as having a virus?Mark Sullivan" ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus on Simanis Orchids site
Did you notify them that this had happened. I have found that lots of sites in some areas of the world are subject to lots of hacking and can have Trojans or other programs installed by them without the owners knowledge. I have even seen it happen to severs at various institutions in the U.S. At 11:47 AM + 1/26/06, Oliver Sparrow wrote: >A warning: I browsed (26 Jan 06) the Simanis Orchids (Indonesia) site - for >which I am *not* going to give a URL - and it immediately tried to download a >trojan virus onto my computer. Fortunately I have heavy duty protection and it >did not get anywhere, but others may be less protected. >__ > >Oliver Sparrow >+44 (0)20 7736 9716 >www.chforum.org > > >___ >the OrchidGuide Digest (OGD) >orchids@orchidguide.com >http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com -- --Tom / | Tom HillsonAgriculture Computer Services Manager |(515) 294-1543 College of Agriculture | Iowa State University - |"The only thing I have too much of is too little time" ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus on Simanis Orchids site
A warning: I browsed (26 Jan 06) the Simanis Orchids (Indonesia) site - for which I am *not* going to give a URL - and it immediately tried to download a trojan virus onto my computer. Fortunately I have heavy duty protection and it did not get anywhere, but others may be less protected. __ Oliver Sparrow +44 (0)20 7736 9716 www.chforum.org ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] virus....the computer kind
Eric, I have been "visited by the Germans" as well, but those emails have come to a work email address that nobody here has ever seen, while I've gotten none at this address... Ray Barkalow - First Rays Orchids - www.firstrays.comPlants, Supplies, Artwork, Books and Lots of Free Info! - Original Message - From: e.muehlbauer To: Orchids@orchidguide.com Sent: Wednesday, May 18, 2005 9:24 PM Subject: [OGD] virusthe computer kind I guess that one of those viruses is out there again (as usual?), the kindthat copy address books and send out loads of garbage in the names of peoplein them...I have been hit by loads of "mail returned" ,etcnot to mentionlots of it spam...most of it German. Included with the mail return messagesare several from this list, OGD. My guess is the virus must have hit someoneon this list, probably in Europe. (I have run quite a few virus checksmyself...so far I'm clean). My apologies to anyone who is receiving anyemail's from my addressI didn't send them. No blame for the person whogot the virus...these things happenI just delete all the spam andreturned stufff from webmail without even downloading it. Take care, EricMuehlbauer in cool but beautiful Queens NYCyp pubescens looking great inthe backyard___the OrchidGuide Digest (OGD)orchids@orchidguide.comhttp://orchidguide.com/mailman/listinfo/orchids_orchidguide.com ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] virus....the computer kind
I guess that one of those viruses is out there again (as usual?), the kind that copy address books and send out loads of garbage in the names of people in them...I have been hit by loads of "mail returned" ,etcnot to mention lots of it spam...most of it German. Included with the mail return messages are several from this list, OGD. My guess is the virus must have hit someone on this list, probably in Europe. (I have run quite a few virus checks myself...so far I'm clean). My apologies to anyone who is receiving any email's from my addressI didn't send them. No blame for the person who got the virus...these things happenI just delete all the spam and returned stufff from webmail without even downloading it. Take care, Eric Muehlbauer in cool but beautiful Queens NYCyp pubescens looking great in the backyard ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] VIRUS CONTROL
I have enjoyed, and benefited from, the exchange of messages on virus control. While not a complete fanatic on the subject of greenhouse sanitation, I do make some effort to maintain a virus-free collection. On the specific subject of tool sanitation, I find the following excerpt from a recent message rather puzzling: >Another result of this discussion is: a saturated solution of Tri>Sodium Phosphate is an ineffective way to sterilize tools and is strongly>recommended against by some of the professional microbiologists on the list.>This agrees with my poorly remembered chemistry. Bleach solution is a good>alternative and will not corrode your tools any faster than the TSP. I have no argument with the statement that a bleach solution is effective in virus control. However, I have seen no information to support the statement that a saturated solution of TSP is "ineffective." First, a lot of "published literature" states that soaking tools in a saturated solution of TSP is an effective method of virus control. See, for example Wisler, How To Control Orchid Viruses, Maupin House, 1989, "Another good dip for tools and pots is a saturated solution of trisodium phosphateThe high pH, like a bleach solution, will inactivate the virus particles." Essentially the same statement is made in the AOS booklet on Orchid Pests and Diseases. Furthermore, my own experience is that a saturated solution of TSP is much less corrosive to tools than a bleach solution. So what is a poor amateur, lacking an extensive education in biology and chemistry, to believe? Giles Smith ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
Re: [OGD] Virus infectivity
Title: Re: [OGD] Virus infectivity The discussion on viruses got me thinking about the virus lectures we had in a Plant Pathology course I took 35 years ago. I dug up my old note book, who knows why I kept it. One of the paragraphs I wrote in my notes relates to using milk to block the infection of TMV. Field workers on many tobacco farms smoked during the 60's and the supervisors trying to keep the fields clean would have them all wash their hands and boots with a mixture of powered milk. The idea was that the milk protein would coat the virus particles on the worker and inhibit infection of the plants they were working on. To see if this was still thought of as true, I did a quick search and found this article. http://www.gov.on.ca/OMAFRA/english/crops/facts/01-017.htm It had this on working with tomatoes to prevent virus infection Dip tools and gloved hands in undiluted skim milk or virucidal disinfectant between every plant. The skim milk should contain at least 3.5% protein, and as soon as the milk starts to go sour, or curdles, replace with fresh milk. It has a lot of other recommendations. Would this work on orchids, who knows? If you have some virus infected plants or you are worried about viruses, try it and see what happens. -- --Tom / | Tom Hillson Agriculture Computer Services Manager |(515) 294-1543 College of Agriculture | Iowa State University - |"The only thing I have too much of is too little time" ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus infectivity
"Mr Richard Thomson" <[EMAIL PROTECTED]> spaketh thusly: > Hi all, I am seeking a better understanding of some > aspects of virus that effect orchids. I understand that > the virus can remain as a protein type material in dead > plant tissue indefinitely. And also, perhaps in potting > media. And reactivates when it comes in contact with > plant material. > Perhaps my understandings are not correct. I think you'd have to specify which virus or viruses concern you. Some plant viruses are remarkably stable; one strain of a tobacco tobamovirus demonstrated infectivity from pressed herbarium specimens that were 45 years old (Randles, Search 2: 30, 1971). On the other hand, cymbidium mosaic potexvirus live no more than 25 days without a host (Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J., Watson, L. and Zurcher, E.J. (eds.) (1996 onwards). `Plant Viruses Online: Descriptions and Lists from the VIDE Database. Version: 20th August 1996). But cymbidium ringspot tombusvirus can live as long as 300 days (ibid). There are no data on the LIV (longevity of infectivity) for odontoglossum ringspot tobamovirus, at least as I can find. Given the longevity of other tobamoviruses, it could be infective for years as the stability of this family of viruses is remarkable. Others are quite short-lived; vanilla necrosis potyvirus has an LIV of 1-2 days (ibid). Look at it this way: common cold viruses are relatively short-lived outside the host, with rhinoviruses lasting on the order of minutes. Hepatitis, on the other hand, can last 14 days on a clean, dry surface with nothing more than old back issues of "People" magazine to read. Given the number of viruses that infect orchids at least occasionally, and that at least some of these viruses are particularly long-lived in the absence of a living host, there are certain precautions that should be taken. I recommend burning your collection annually, and start with new plants at least once a year. Fire is strong medicine, but it cures all ills. Except maybe prions. Cheers, -AJHicks Chandler, AZ ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus alert ... it's a hoax
"Raphael & Chawadee Verkest" posted a "NEW VIRUS ALERT!!!" regarding the "life is beautiful" virus. There is no such virus. It is a hoax. Check: http://securityresponse.symantec.com/avcenter/venc/data/life.is.beautiful.hoax.html Peter O'Byrne in Singapore ___ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
[OGD] Virus risks
>"..I trust you and thank you for the advice!"
Albeit with admiration and appreciation for the technical commentary on this
subject from list participants, I respectfully take exception to the
apparently dominant opinion on the efficacy of bleach as a reliable virus
sterilant for orchid pots and cutting instruments. Relying on my long-term
practical experience in protecting valuable plants from infection with
orchid viruses, I conclude that bleach (derived from either calcium or
sodium hypochlorite compounds) DOES NOT reliably eliminate virus
transmission risks. For reference, please see virologist, Dr Gail Wisler's
volume on the subject ... "How to Control Orchid Viruses - The Complete
Guidebook" (ISBN 0-929895-00-2). Dr F William Zettler, distinguished
virologist (now retired, I believe) at the Univ of Florida worked with
orchidists in Florida and elsewhere during the 70's and 80's to understand
the practical and technical issues of virus transmission; he was a leader in
elevating awareness about the problem among commercial orchidists in
particular. Dr Wisler, currently chairman of the Department of Pathology at
the Univ of Florida, insisted in her guide that bleach is NOT reliable for
virus sterilization. Furthermore, she chronicled the history of one project
in which a hobbyist's collection was almost completely freed from infection
(using elimination of infected stock and sound cultural practices) in less
than five years.
Realizing that there are no "do-overs" in dealing with this critical
challenge ("Once infected, always infected!"), I rely on heat to sterilize
both my clay pots and work tools. A handy torch works nicely for both the
business end of my shears (by-pass style), or wire stakes and hangers; and a
potter's kiln is perfect for batches of clay pots. TSP can be used for
tools/stakes as well (See Wisler above)but exercise great caution to be
sure the instruments a cleaned thoroughly before placing them in the
super-saturated TSP solution.
You can reliably enjoy virus free orchids with these careful sanitation
practices.
Bob Scully
Sarasota, FL USA
[EMAIL PROTECTED]
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