Greetings All:
The purpose of this message is to bring awareness and resolution to an unidentified pathogen that has the ability to severely impact the entire cannabis industry and likely already is. Cases are confirmed in California and Colorado.
Below is a clear description of the symptoms this plant pathogen causes and supporting information, pictures and links to help identify it. We hope to use our community of breeders, growers, pathologists and scientists to solve this problem before it becomes an epidemic.
First off, we are not pathologists, we are independent researchers and farmers, but we feel confident that this pathogen is a virus. It causes massive crop loss, widespread reduction in yields and may well be causing high concentrations of calcium oxalate crystals in cannabis, which is harmful to humans. The following is a summary of symptoms of the disease caused by this pathogen:
In Veg:
- Lack of apical dominance. Plants sometime grow wider than tall.
- No normal large fan leaf growth. Leaves are generally small and blades tend to point upward with an overall “spiky” appearance.
- The plants have an unusual branch structure, sometimes referred to as “witch-brooming.” Branches often bow down instead of growing up at a steep angle.
- Short spacing in between nodes, often bunching up with a section of unusually colored stem.
- Very brittle stems. Branches are thin, weak and rubbery and easily break off and flop around.
- General lack of vigor and water uptake is impaired.
In Flowering:
- Overall irregular development. Plants look impaired, behind schedule, and flowers are generally “larfy.” .
- Slow metabolism. Lack of water uptake.
- Chlorosis/yellowing. Tends to look nitrogen deficient. This starts at the bottom and moves upward.
- Lack of resin and trichome production. Weak smell.
- Leaf death
- Wilting and often total plant death over time.
**Thanks OnTheCrush
The disease caused by this pathogen is often mistaken for broad mite infestation. This is not a broad mite problem. Infected plants have tested clean for insects, mites of all kinds and for all the major fungal infections, including: Pythium, Fusarium, Rhizoctonia, Verticillium, and Phytophthora.
Infected plants have however, tested positive for Tobacco Mosaic Virus (TMV). Several online message threads have this disease as labeled “duds” or “duds syndrome.” Attached below are links to several relevant threads that illustrate the severity of this problem. There is no evidence that TMV causes “Duds,” just that TMV was confirmed in some samples from plants infected with “Duds.”
There seems to be a higher visible infection rate amongst farmers that keep mother plants of popular genetics, particularly, Gorilla Glue #4, OG, Girl Scout Cookies and Sour Diesel. People who clone from previous generations before flowering tend to have far less concentrations of visible infection. This does not mean the plants aren’t infected or that yields are not reduced substantially.
Our goal with this message is to find people, farmers and professionals that can help identify and solve this problem before it gets worse. Also, if any existing stocks of uninfected major genetic lineages can be identified, it is prudent that they be protected and preserved before they are exposed. If you think you’ve experienced this problem, please respond to this message with any information about your experience you’re willing to provide.
Healthy on left, infected on right (in veg)
Healthy on left, infected on right (in flower)
Links with valuable information and history:
https://www.thcfarmer.com/community/threads/co-dud-collective.73664/
https://www.icmag.com/ic/showthread.php?t=285743
https://www.thcfarmer.com/community/threads/what-to-do-with-duds.64342/
www.thcfarmer.com
