Although there are no cases of TMV infecting cannabis or hemp plants in the literature, many growers suspect TMV in plants that develop a mosaic-like pattern of discoloration on the leaves that cannot be attributed to nutrient deficiencies. Our team has screened several suspected TMV plants only to find Hop Latent Viroid. While this does not rule out the possibility of TMV infecting cannabis and hemp plants, we have not been able to confirm an infection, yet. Perhaps you will be the first!
Tobacco mosaic virus symptoms observed in other plants include mosaic, mottling leaves, necrosis, stunting, leaf curling, and yellowing of plant tissues. In fruiting plants, TMV infection can also cause reduced yield and poor fruit quality.
TMV spreads primarily via direct contact with an infected plant. Plants that rub against each other transmit TMV, as well as hands that have touched an infected plant. It is also possible that people who consume tobacco products can spread the virus to plants. TMV is exceptionally stable, and purified virus has been reported to be infectious after 50 years storage in the laboratory at 4°C.
Growers typically remove any plants infected with TMV because there is no cure. Growers should screen mother plants with qPCR tests to make sure any cuttings that are taken will be virus-free. Cultivators can also screen incoming clones with qPCR assays to make sure they are not introducing infected plants to their grow.
Medicinal Genomics offers a variety of PathoSEEK qPCR assays for plant pathogens, including Tobacco Mosaic Virus. DNA can be extracted from infected fan leaves using the Leaf Punch Lysis, and the detection assay can be run on the Agilent AriaMX and BioRad CFX96.