[VerdantGreen]

Hi all, there is a thread about symptoms etc in the infirmary but i would say many of the pics or reported cases in there may be some other plant problem. i have been trying to look into this for a while now since being lucky enough to acquire the Chem D clone which is supposed to have this virus. the main things i have found out are pretty negative - you cant cure it, it can be passed on through insect vectors and seeds made from infected parents.
the only leads i found are that seeds can possibly be heat treated to kill the virus, and that maybe salicylic acid could be a way to kill the virus in live plants, maybe.
so i thought i would start a thread here in the hope that someone may know some facts about this...
https://en.wikipedia.org/wiki/Tobacco_mosaic_virus

some questions i have are....

1. has this virus actually been confirmed in Chem D? to my eye it could be a genetic trait, like a variegation. i havent seen any lack of vigor in the plant but apparently it slows down rooting (i'll report back about that )

2. are there any proven or possible ways of curing it - either in seed stock or live plants?

3. how much should we be concerned about it/ its spread and it's perpetuation through breeding.

thanks

VG

[TacomaComa]

im about to aquire the D cut and would like to know the answer to these same questions.

[Sam the Caveman]

I had several different strains that had potato leaf crinkle, which is much more deliblitating than TMV and is also a virus. Salicylic acid worked wonders, it was amazing how the plants recovered and they are near chop right now with seemingly no ill effect. Nice yields and great looking plants. I will say that all the infected leaves eventually died, so if you see a tmv leaf, spray SA and remove the effected leaves. I have seen some leaves that were effected recover from tmv looking leaves but they never looked normal, slight contorted but seemingly functional.

I have a link in my sig about using sa.

[!!!]

No way to cure the plant of the virus, but if you want to save the genetics, you can take a tiny snip of the very top of the new growth of the plant and cultivate it in vitro (cell culture.)

The idea behind this is that the virus propagates slower than the plant grows, so very new growth should be virus free.

I personally have an issue that is yet undiagnosed. I have since given up on it just because it doesn't seem to affect vigor too much. Here are shots of my leaves in veg:


Notice the bite marks/rips on the leaves. There are no insects except some gnats, no leaf minors, and no physical damage being done to the leaves.

They turn out very normal dark and thick in flowering:


but if you see the top of the plants, some of the leaves bleach. Maybe light bleaching but they are streaks of yellow. This is a symptom of the virus but in my case it's likely something else. I'll try to get a picture next time I'm in the garden.

IF you have it, you have it forever until you eradicate it. This means tossing pretty much everything in the garden, every clone and seed from infected plants, sterilizing the equipment, probably best to toss out nutes and additives also unless you can be sure they're clean. Avoid tobacco use in the garden, use sanitizer before/after work, don't let strangers come touch your plants and keep anything used in outdoor gardening away from the grow.

Chem D probably just has variegation. If it had the virus, it would spread to every other plant in the grow in a shared res system or if fungus gnats and other vectors are present. Since I see pics of people with chem D next to healthy plants, it's probably not a big deal.

[OsWiZzLe]

the Plant can be cured.....i dont know how it works....but i have taken many many many ChemD clones and I have seen it not show up in cuttings ...dont know who this happens...but 100% for a fact i have seen it go away

[northstate]

Hello to VG and good questions. The Chem, OGK and many Diesel genes we have run appear to have the TMV?/ varigated leaves when they are young and seem to grow right through it with no ill affects. It will show from time to time throughout the cycle but very tiny areas on fans but I think it could be genes as opposed to a virus...Good food for thought it does remind me of some of DJ's blue with its light look and such......Cheers, NS

[VerdantGreen]

thanks for posting northstate.

i was looking at the chem 101 thread and many of the pics of chem D in the thread dont appear to have the leaf colour/virus 'trait' showing at all. the thread was from '07 and the pics maybe older than that...
https://www.icmag.com/ic/showthread.php?t=60048

i might have a mess about with some aspirin/salicylic acid on a rooted cut and see if it does anything
does anyone know how many aspirin to how much water for a good strong dose?? (that wont kill the plant??_)

VG

[spurr]

Originally Posted by Sam the Caveman

I had several different strains that had potato leaf crinkle, which is much more deliblitating than TMV and is also a virus. Salicylic acid worked wonders
I have a link in my sig about using sa.

That is what I was about to write, SA has been found to inhibit Mosaic virus. I am not sure of its efficacy once the plant has MV, though.

[spurr]

Originally Posted by VerdantGreen

thanks for posting northstate.


i might have a mess about with some aspirin/salicylic acid on a rooted cut and see if it does anything
does anyone know how many aspirin to how much water for a good strong dose?? (that wont kill the plant??_)

VG

You can use ~100 ppm SA, well, that is the dosage commonly most used for SA to induce SAR. I have at lest one study looking at SA effects upon Mosaic virius IIRC; I can check it out and see what application rate the researchers used. FWIW, aspirin does not contain SA, only its acetate: "acetylsalicylic acid". That said, ASA has been found to effect plants in the same manner as SA in terms of SAR; I am not sure if the analog also hinders MV like SA.

[spurr]

@ VG,

Here are some studies you may want to check out, and one even using aspirin (acetylsalicylic acid, i.e., salicylic acid acetate). It appears SA and ASA can hinder MV (TMV and CMV) even after infection. Something worthwhile to point out is an excerpt from a study:


"Salicylic Acid-Induced Resistance to Cucumber mosaic virus in Squash and Arabidopsis thaliana: Contrasting Mechanisms of Induction and Antiviral Action"
Carl N. Mayers, Kian-Chung Lee, Catherine A. Moore, Sek-Man Wong and John P. Carr
MPMI Vol. 18, No. 5, 2005, pp. 428–434
(full text) https://apsjournals.apsnet.org/doi/pd...4/MPMI-18-0428

The results show that different host species may use significantly different approaches to resist infection by the same virus. These findings also imply that caution is required when attempting to apply findings on plant–virus interactions from model systems to a wider range of host species.

2. "Salicylic Acid Has Cell-Specific Effects on Tobacco mosaic virus Replication and Cell-to-Cell Movement"
Alex M. Murphy and John P. Carr
Plant Physiol, February 2002, Vol. 128, pp. 552-563
(full text) https://www.plantphysiol.org/cgi/cont...ract/128/2/552

Therefore, it appears that SA has distinct cell type-specific effects on virus replication and movement in the mesophyll and epidermal cell layers, respectively. Thus, SA can have fundamentally different effects on the same pathogen in different cell types.

3. "Acetylsalicylic acid (aspirin) induces resistance to tobacco mosaic virus in tobacco"
R. F. White
Virology Volume 99, Issue 2, December 1979, Pages 410-412
(abstract only for now; I can get full text later today) https://www.sciencedirect.com/science...7&searchtype=a


4. "Salicylic Acid Interferes with Tobacco Mosaic Virus Replication via a Novel Salicylhydroxamic Acid-Sensitive Mechanism"
S. Chivasa, A. M. Murphy, M. Naylor and J. P. Carr
THE PLANT CELL, Vol 9, Issue 4 547-557 (1997)
(full text) https://www.plantcell.org/cgi/content/abstract/9/4/547