if all goes well i should be getting my chem d tested for mosaic virus in a lab soon...
i'll post the results.
VG
i'll post the results.
VG
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Mosaic virus and Cannabis, Chem D etc...
- Thread starter VerdantGreen
- Start date
Wow. Just stumbled across this thread today.
I propagate plants in sterile tissue culture for a living. One of the first things we do is index plants before cloning them; indexing for viruses can be done several different ways- more on that in a moment. However, it is important that plants be tested for viruses prior to multiplying them for several reasons- not the least of which is that when growing well, plants can be asymptomatic. Problem is, if they're stressed, the effects of the virus can surface, and decimate a crop. Think of it like cold sores: lots of people carry them, but they're not always visible. Worse, when the plants are propagated clonally, a single infected plant can reduce an entire greenhouse to bankruptcy if things are bad enough. It can get even worse if other susceptible crops in adjacent growing facilities are infected by vectors such as aphids.
That said, it's quite possible the effects that are being seen are a virus- just not tobacco mosaic virus. This could explain why the effects of a virus are observed, but repeated ELISA and Agdia immunoassays are coming up negative. It could be another tobamovirus, or another viral "genus" entirely. If this is the case, then the only true way to detect these viruses is with scanning electron microscopy- although that is hit-or-miss because viral loads can be small enough as to be undetectable at this level.
There is one trick that has not been discussed that serves almost as well as SEM, and is more useful than ELISA or other immunoassays: indicator plants. There are some plants that are susceptible to damned near every virus that comes along, forming necrotic lesions when the sap of an infected plant is rubbed into a leaf that has been wounded with sandpaper. I seem to recall the most common is Cassia occidentalis (coffee senna), although there are several. The main caveat is that a susceptible cultivar must be selected; over the years, some of these plants have been selectively bred for virus resistance.
While plants do not have a seek-and-destroy immune system like mammals, many are capable of defending against systemic viral infection by "walling off" and killing areas that are affected. These indicator plants do just that, and a single plant can be used for multiple tests. However, with many crop/virus combinations, the virus is transmitted systemically. While it has been suggested that meristem propagation may yield virus-free clones, this is done only in conjunction with testing. Often, the process is performed in conjunction with heat treatments and exposure to anti-viral compounds in order to reduce the chances of a virus being passed along. Trimming visibly affected areas will not rid a plant of virus.
Bear in mind that if there IS an infected plant in a collection, casual disinfection practices such as alcohol, quats (such as Physan), and even bleach may not be sufficient to assure 100% denaturation of virus particles on cutting tools. For this, there is only one 100% effective practice: thermal treatment, which would include heating to well above autoclave temperature. (TbMV is very odd in that it can re-form from its thermally shattered components, up to some temperature that is well above where you'd think it would be. Precise figures escape me.) All cutting tools I use are heated to 230C before re-use. Use of disinfection solutions including alcohol and quats may just spread the problem as they do not denature viruses reliably. Note that while Physan *claims* it is viruscidal, this claim comes from a single paper done on beans back in the 1960s, and that was never published in a peer-reviewed journal.
Some sources suggest that saturated trisodium phosphate solution- in conjunction with scrubbing- may be adequate to assure control of viruses on cutting tools. I don't know of any papers on the subject. Others suggest milk may work; however, others have suggested that perennials propagated in this fashion may show signs of virus because the antibodies that stick to the virus particles "wear off" after some time. For crops like cannabis that are handed down through multiple generations, this may be a consideration. For surface disinfection, bleach is probably the next best thing.
So- I think there are several issues here:
1) Identifying the presence/absence of a true plant virus, versus symptoms of physiological or pest problems
2) Identification of a possible agent other than TbMV
3) Recognizing that "casual" techniques in preventing spread of such viruses may be less effective than would be desired in high-value crops
4) Recognizing that treatment of infected crops may be undesirable; prevention is key
I propagate plants in sterile tissue culture for a living. One of the first things we do is index plants before cloning them; indexing for viruses can be done several different ways- more on that in a moment. However, it is important that plants be tested for viruses prior to multiplying them for several reasons- not the least of which is that when growing well, plants can be asymptomatic. Problem is, if they're stressed, the effects of the virus can surface, and decimate a crop. Think of it like cold sores: lots of people carry them, but they're not always visible. Worse, when the plants are propagated clonally, a single infected plant can reduce an entire greenhouse to bankruptcy if things are bad enough. It can get even worse if other susceptible crops in adjacent growing facilities are infected by vectors such as aphids.
That said, it's quite possible the effects that are being seen are a virus- just not tobacco mosaic virus. This could explain why the effects of a virus are observed, but repeated ELISA and Agdia immunoassays are coming up negative. It could be another tobamovirus, or another viral "genus" entirely. If this is the case, then the only true way to detect these viruses is with scanning electron microscopy- although that is hit-or-miss because viral loads can be small enough as to be undetectable at this level.
There is one trick that has not been discussed that serves almost as well as SEM, and is more useful than ELISA or other immunoassays: indicator plants. There are some plants that are susceptible to damned near every virus that comes along, forming necrotic lesions when the sap of an infected plant is rubbed into a leaf that has been wounded with sandpaper. I seem to recall the most common is Cassia occidentalis (coffee senna), although there are several. The main caveat is that a susceptible cultivar must be selected; over the years, some of these plants have been selectively bred for virus resistance.
While plants do not have a seek-and-destroy immune system like mammals, many are capable of defending against systemic viral infection by "walling off" and killing areas that are affected. These indicator plants do just that, and a single plant can be used for multiple tests. However, with many crop/virus combinations, the virus is transmitted systemically. While it has been suggested that meristem propagation may yield virus-free clones, this is done only in conjunction with testing. Often, the process is performed in conjunction with heat treatments and exposure to anti-viral compounds in order to reduce the chances of a virus being passed along. Trimming visibly affected areas will not rid a plant of virus.
Bear in mind that if there IS an infected plant in a collection, casual disinfection practices such as alcohol, quats (such as Physan), and even bleach may not be sufficient to assure 100% denaturation of virus particles on cutting tools. For this, there is only one 100% effective practice: thermal treatment, which would include heating to well above autoclave temperature. (TbMV is very odd in that it can re-form from its thermally shattered components, up to some temperature that is well above where you'd think it would be. Precise figures escape me.) All cutting tools I use are heated to 230C before re-use. Use of disinfection solutions including alcohol and quats may just spread the problem as they do not denature viruses reliably. Note that while Physan *claims* it is viruscidal, this claim comes from a single paper done on beans back in the 1960s, and that was never published in a peer-reviewed journal.
Some sources suggest that saturated trisodium phosphate solution- in conjunction with scrubbing- may be adequate to assure control of viruses on cutting tools. I don't know of any papers on the subject. Others suggest milk may work; however, others have suggested that perennials propagated in this fashion may show signs of virus because the antibodies that stick to the virus particles "wear off" after some time. For crops like cannabis that are handed down through multiple generations, this may be a consideration. For surface disinfection, bleach is probably the next best thing.
So- I think there are several issues here:
1) Identifying the presence/absence of a true plant virus, versus symptoms of physiological or pest problems
2) Identification of a possible agent other than TbMV
3) Recognizing that "casual" techniques in preventing spread of such viruses may be less effective than would be desired in high-value crops
4) Recognizing that treatment of infected crops may be undesirable; prevention is key
Hey! My ego is making me point out that I suggested trying to infect ornamental tobacciana with material from the suspected host plant strained through mesh fine enough to exclude bacteria.
The articles I read regarding Tospoviruses mentioned using indicator plants in the greenhouse to alert the grower to the presence of virus infected thrips. This is comparable to using the proverbial "canary in a coal mine". Petunias are supposed to show symptoms of infection before the crop plants do. Petunias were also mentioned for innoculation tests with TMV.
A quick googling brought up these articles with photos;
http://www.hort.uconn.edu/ipm/greenhs/htms/tospov.htm
http://www.umass.edu/umext/floriculture/fact_sheets/pest_management/virusind.html
http://www.flora-links.org/petuniaindicators.htm
A quick googling brought up these articles with photos;
http://www.hort.uconn.edu/ipm/greenhs/htms/tospov.htm
http://www.umass.edu/umext/floriculture/fact_sheets/pest_management/virusind.html
http://www.flora-links.org/petuniaindicators.htm
Ah! Apologies; long thread, and I confess I skimmed a few posts.
Nicotiana is certainly a vulnerable genus when it comes to viruses. In fact, all of the Solanaceae is a target, it seems. Using it as an indicator plant has one problem: the virus may be asymptomatic. The "classic" indicator plants demonstrate local necrosis, usually rather quickly. Other plants may be prone to continuing on without symptoms of infection unless they're stressed- and the stress alone may mimic viral infection. Similarly, there's a chance the cultivar used as an indicator plant may have been bred for virus resistance- same as any other indicator plant, of course.
FWIW, the family of interest seems to be largely unexplored with respect to susceptibility to viruses.
I think this is a very important statement for discussion. I have seen multiple time folks claim they can cure a plant by removing effected areas and/or taking cuts from (seemingly)non-effected areas.
I think we also need to consider if the visible afflictions can be attributed to genetics, or even a hormonal display.
Agreed. As is the case with any crop, sometimes the plants present with cryptic symptoms that are a combination of genetics and stress. In the case of cannabis, the stressors are many as the grower endeavors to produce larger amounts of product. And it would be unreasonable to expect different clones or hybrids to respond the same to viruses.
Plant viruses are a very messy subject, and there's a lot of scuttlebutt and rumor. Very few people have the time or desire to get to the bottom of a problem, and quite reasonably so: they just want it to go away.
I can show a line that has mutation in it's map.
I have been growing f13 for a couple years now. One of the original F1's displayed heavy mutation and was not much of a producer. And another sister plant was very uniform and showed no signs of the mutation.
I used the uniform displaying plant for an outcross. The progeny of that cross shows a very high rate of mutation. One would have thought it was the mutated sister that was bred, rather than the uniform plant. (which brings me to points considering the numbers used when making an outcross..but I digress)
Anyway, this same uniform plant was flowered out 2 years ago and has been a clone mom ever since. Just recently I took some cuts and one of them displayed what a full on reveging plant would. Gnarly, curled up, waxy leaves..the whole nine yards. In fact, it was hard to distinguish that it was even a cut of the F13. I was questioning my labeling.
But the cut finally straightened out, like a reveg would, and is now growing quite normal.
Not sure what triggered the hormonal response in that cut, as other cuts of same size, same bubbler, did not display this.
Folks unfamiliar with the mutation that the line carries could possibly think they are seeing a virus.
I have been growing f13 for a couple years now. One of the original F1's displayed heavy mutation and was not much of a producer. And another sister plant was very uniform and showed no signs of the mutation.
I used the uniform displaying plant for an outcross. The progeny of that cross shows a very high rate of mutation. One would have thought it was the mutated sister that was bred, rather than the uniform plant. (which brings me to points considering the numbers used when making an outcross..but I digress)
Anyway, this same uniform plant was flowered out 2 years ago and has been a clone mom ever since. Just recently I took some cuts and one of them displayed what a full on reveging plant would. Gnarly, curled up, waxy leaves..the whole nine yards. In fact, it was hard to distinguish that it was even a cut of the F13. I was questioning my labeling.
But the cut finally straightened out, like a reveg would, and is now growing quite normal.
Not sure what triggered the hormonal response in that cut, as other cuts of same size, same bubbler, did not display this.
Folks unfamiliar with the mutation that the line carries could possibly think they are seeing a virus.
that's kinda like one of my blue sats!
This is one of the mutant siblings that I flowered out. Notice how the mutation manifests itself on an individual branch, while other branches show no signs of the trait.
None of the nodes on this branch show mutation...
yet this branch every node is mutated.
It would be easy to think this plant had a virus on an effected area. But knowing the line, I know that is not the case here.
I find it very interesting how a mutation can appear in selective areas.
This is the above mutant bud dried out...
None of the nodes on this branch show mutation...
yet this branch every node is mutated.
It would be easy to think this plant had a virus on an effected area. But knowing the line, I know that is not the case here.
I find it very interesting how a mutation can appear in selective areas.
This is the above mutant bud dried out...
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Earlier in the thread I tested my Chem D cut with a TMV test kit, it came out negative and some said well I heard it is only on some cuts (lines). My chem D cut had displayed some slight variations in the leaves in flower, and looks like classic TMV symptoms. So I think we can safely say it is simply genetics when it comes to the Chem D, since she has already tested negative.
hey PK when you say that do you mean your cut has this leaf variegation trait like in the pic?
VG
Like i said earlier Chem D does not have TMV, it would infect everything it comes into contact with and it doesnt.
TMV is all through my garden new seedlings infected along with all out sourced clones, it spreads very easily.
i finally got the 'nod' to send in a leaf sample of Chem D for mosaic virus testing... it sounds like it will be a pretty definitive test. big thanks to the guy who sorted this out for me. i wont namecheck him but he's welcome to come and take a bow if he chooses 
if all goes well i should have some results soon...
VG
if all goes well i should have some results soon...
VG
Mosaic virus and Cannabis, Chem D etc...
Thsts rad VG
....staying tuned....
i finally got the 'nod' to send in a leaf sample of Chem D for mosaic virus testing... it sounds like it will be a pretty definitive test. big thanks to the guy who sorted this out for me. i wont namecheck him but he's welcome to come and take a bow if he chooses
if all goes well i should have some results soon...
VG
Thsts rad VG
....staying tuned....
i finally got the 'nod' to send in a leaf sample of Chem D for mosaic virus testing... it sounds like it will be a pretty definitive test. big thanks to the guy who sorted this out for me. i wont namecheck him but he's welcome to come and take a bow if he chooses
if all goes well i should have some results soon...
VG
Any update on this VG?
Cheers
Smiley
hi George, unfortunately, despite sending a sample twice, i never got the results from the guy who offered to test this for me.
fwiw, having kept a mum of the chem D for some time now in very close contact with my other mums - and having seen Chem D progeny inherit similar leaf traits - im pretty confident that it isnt TMV.
VG
fwiw, having kept a mum of the chem D for some time now in very close contact with my other mums - and having seen Chem D progeny inherit similar leaf traits - im pretty confident that it isnt TMV.
VG
theres an online testing lab that has a test kit.
you get 5 individual test packets
$27 +shipping
I ordered it, fast and easy, and just the peace of mind knowing is worth that alone
FRANKIE1579
Member
Just wanted to let people know results. I tested POSITIVE for TMV with the agdia testing strips. Multiple test kits used, used control plants from other locations as well and no positive results.
I destroyed EVERY plant I had. There was one strain I refused to lose as I am only one of 2 people who have it, but managed to get a new cutting so everything got the chop. Lights were left running in rooms on a 95F + day with no ventilation. Got up to the 130's for several hours. Bleached and boiled every single root pot and every piece of cutting, pruning equipment.
6 months later no signs. Root aphids still around so the fight goes on, but the weird twisty leaves and fucked up growth has left ever since tear down and disinfection.
I destroyed EVERY plant I had. There was one strain I refused to lose as I am only one of 2 people who have it, but managed to get a new cutting so everything got the chop. Lights were left running in rooms on a 95F + day with no ventilation. Got up to the 130's for several hours. Bleached and boiled every single root pot and every piece of cutting, pruning equipment.
6 months later no signs. Root aphids still around so the fight goes on, but the weird twisty leaves and fucked up growth has left ever since tear down and disinfection.
Some old dude
Member
I have virus still (I think)
I have virus still (I think)
(35 year grower) I brought in infected cut years ago. Went absolutely crazy for a couple years.Sterilized everything. Threw away Everything Mother plants, all plants, all hydro equipment Rez, pots tools everything (Big loss)..Started with "New everything' (Big cost)...Had two good grows (no sign at all of a virus)..Now seeing same type of dead area's and twisting and blemishes on mothers. Then A light bulb over my head appeared. The worse vectors for plants are "BUGS" obviously I did not realize 99 percent of grows get flying bugs going in and out of the grows it just can't be helped .Or microscopic eggs ect, I went out in yard and noticed some of my plants in the yard had the exact same ragged cut leaves and mottling patterns. "Summation" ...If you ever get it you will always have it until you move.
I have virus still (I think)
(35 year grower) I brought in infected cut years ago. Went absolutely crazy for a couple years.Sterilized everything. Threw away Everything Mother plants, all plants, all hydro equipment Rez, pots tools everything (Big loss)..Started with "New everything' (Big cost)...Had two good grows (no sign at all of a virus)..Now seeing same type of dead area's and twisting and blemishes on mothers. Then A light bulb over my head appeared. The worse vectors for plants are "BUGS" obviously I did not realize 99 percent of grows get flying bugs going in and out of the grows it just can't be helped .Or microscopic eggs ect, I went out in yard and noticed some of my plants in the yard had the exact same ragged cut leaves and mottling patterns. "Summation" ...If you ever get it you will always have it until you move.
