Robert Bergman (author of the grow bible) seem to be under the impression that this needs to be contained and that it spreads very easily. I actually laughed a little while reading this
It seems a little bit too much to me:
Tobacco Mosaic Virus On Marijuana Plants
Robert Bergman
In this article we will discuss:
What is the tobacco mosaic virus?
Signs of TMV
How to cure TMV
Marijuana plant symptoms
The tobacco mosaic virus (TMV) is a disease that attacks not only marijuana plants, but also tomato, pepper, eggplant, tobacco, spinach, petunia, and marigold.
It isn't very selective, but it does have a high impact. Read this article and learn how to recognize and treat TVM.
What is the tobacco mosaic virus?
What is the tobacco mosaic virus on weed
The tobacco mosaic virus is, as its name hints, a type of virus. It can live in contaminated soil, infected plant debris, the coating of a seed, and even in tobacco products that have been manufactured. The virus travels between plants generally through a mechanical cause.
Your hands can even spread the infection. If you unknowingly work with an infected plant and then come in contact (or your clothes or tools come in contact) with a healthy marijuana plant, the healthy plant has a high chance of catching the virus.
Some insects may also be carriers of the virus, but aphids are not one of them. It's generally insects that will chew on your plant.
Signs of tobacco mosaic virus on weed plants
You will know that your marijuana plant has the tobacco mosaic virus by its green mottled areas on the leaves. These mottled areas are both dark and light green and are caused by the presence of the virus. Oftentimes the dark parts of the leaf are physically thicker than the lighter parts. Additionally, if the leaf is underneath shade than it is easier for the grower to spot the discoloration.
Tobacco Mosaic Virus causes stunted growth in young plants, and may distort the leaves into a fern-like shape. Older leaves, on the other hand, may be a bit distorted, but they mostly just curl downwards.
Depending on the virus strain, buds might also be mottled, streaked, or show signs of necrosis. While plants that are affected won't be killed by the virus, they will have worse buds and, therefore, worse yields. Not sure if your marijuana plants suffer from a TVM infection? Check the article Marijuana diseases for a list with pictures of all possible marijuana diseases
How to cure tvm on cannabis
Unfortunately, once your plants are infected with a virus, there is not much you can do about it. Virus diseases simply can't be controlled once they have been transmitted. This is why it is particularly important to prevent the virus from infecting your plants in the first place.
Your best weapons against the transmitting of this disease are sanitation and caution. If you do discover a plant that has been infected, you should remove it from the rest of your garden at once. If caught early enough, this should stop the spread of the tobacco mosaic virus.
Download my free marijuana grow guide at this link for more growing tips
If you or anyone else uses tobacco or has worked with plant material that was infected, they should wash their hands with soap and water. This will prevent it from spreading to any other plants they are handling.
Marijuana plant symptoms
Leaf Color:
— Brown, burnt edges
— Pale color
— Yellowing of new growth
— Yellowing of lower, older leaves
— Yellowing between veins
— Dark or purple in color
— Black or gray patches
— White powdery patches
— Brown, dark spots
— Mottling, mosaic pattern
Leaf Symptoms:
— Upper, newer growth affected
— Lower, older growth affected
— Burnt leaf edges
— Burnt leaf tips
— Death of leaf tips
— Yellowing between veins
— White powdery patches
— Red stems
— Spots
— Mottling, mosaic pattern
— Old leaves fall off
— Slowed growth
— Twisted, abnormal growth
— Leaves curling under or upwards
— Wilting, drooping
— Webbing on leaves
Plant Symptoms:
— Red or purple stems
— Weakened stems
— Old leaves falling off
— Slowed growth
— Twisted, abnormal growth
— Wilting or drooping
— Slowed root growth
Other Symptoms:
— Webbing
— Bugs
— Mold
— Buds not getting fatter
In case you are someone who uses tobacco practices due to cultural practices, you should avoid these practices altogether while you are growing marijuana plants. The tobacco mosaic virus can sit steadily and stably in manufactured tobacco, so this is a crucial step in preventing the spread of this virus to your plants. It's best to not touch tobacco until the growing season is over.
Remember that plants with strong genetics have less change of getting sick and are less vulnerable for pests and diseases. So make sure to buy marijuana seeds from a trusted seed bank.