Understanding Hop Latent Viroid: A Threat to Cannabis Cultivation

In recent years, a silent yet devastating pathogen named Hop Latent Viroid (HLVd), also referred to as HLV or HpLVd, has emerged as a significant threat to the cannabis industry. Originating from hops, this viroid has found its way into cannabis cultivations, causing a myriad of problems for growers and the industry at large.

What is Hop Latent Viroid (HLVd)?

Hop Latent Viroid is an infectious plant pathogen that targets cannabis plants, causing a disease commonly known as “dudding disease” or just “dudding.” Unlike viruses, viroids are smaller pathogens composed of a single-stranded RNA molecule that uses host plant enzymes to replicate. HLVd can remain latent or inactive within infected plants, making detection without molecular testing almost impossible.

The Impact on Cannabis Industry

The presence of HLV in cannabis plants can be devastating. It’s known to cause stunting, chlorosis, leaf deformation, brittle stems, reduced flower mass and trichome number, significantly altering the typical plant morphology. Once a plant is infected, there’s no eliminating the viroid, which makes it a persistent problem for growers. The viroid’s ability to stay dormant until triggered by stress factors further complicates the issue, often leading to significant losses across cannabis grows.

Studies have revealed that HLV has already caused considerable damage in North America, with estimates suggesting that about 40% of legally sold cannabis flower in Canada might be carrying HLV. This pathogen is not only a concern for individual cultivators but poses a substantial threat to the cannabis industry’s sustainability and growth.

Testing for HLV in Cannabis

Timely detection is crucial to managing and mitigating the impact of HLVd on cannabis cultivations. Various diagnostic testing methods have been developed to identify the presence of HLV in cannabis plants. For instance, the AmplifyRP XRT for HLVd is a kit designed specifically for testing cannabis against the hop latent viroid. The process involves preparing leaf samples, preparing sample extract pouches, preparing test tubes, preparing reaction pellets, and executing the reaction in a machine known as the AmpliFire. This detailed process allows for the rapid testing and detection of HLV in cannabis plants, enabling growers to separate infected plants from healthy ones and stop the spread of HLV.


The emergence of Hop Latent Viroid in cannabis plants has drawn attention to the importance of continuous monitoring and testing in cannabis cultivations. As the cannabis industry continues to expand, developing effective strategies to manage and mitigate the impact of pathogens like HLV will be crucial in ensuring the industry’s sustainability and growth.

For more information and guidance on HLV in cannabis, check the following resources:

  1. Summit Genetics: Testing Cannabis for the Hop Latent Viroid
  2. What is hop latent viroid in cannabis https://cannabistraininguniversity.com/growing/hop-latent-viroid-in-cannabis/

(Note: The links have been verified and are active as of the date of publication. Please check the links for the most recent and updated information.)

The Unseen Enemy: Combatting Fusarium Wilt in Your Garden

Fusarium Wilt is a sinister garden foe. Caused by the fungus Fusarium Oxysporum, it lurks in the soil, attacking the roots of your plants before progressing upward, causing a slow death from the inside out. The damage to agriculture is immense, running into billions of dollars annually, with no fully resistant varieties yet identified.

Recognizing the Enemy

The first step in managing Fusarium Wilt is recognizing its presence. The disease manifests initially in seedlings causing them to collapse due to a type of stem rot. In adult plants, it restricts water flow through stems and leaves leading to yellowing, curling, and wilting of infected branches. The damage usually starts from the lower portion of the plant and travels upwards as the fungus spreads.

Prevention: Your Best Bet

Preventing Fusarium Wilt is far more preferable than treating it since there is no known effective fungicide or cure. Here are some robust preventive measures:

Planting Resistant Varieties

Selecting plant varieties that have a natural resistance to Fusarium Wilt can significantly lower the risk of infection. Even if these resistant cultivars do get infected, they fare much better against the disease than non-resistant ones【13†(Epic Gardening)】.

Crop Rotation

Fusarium fungi can reside in the soil for up to four years. Practicing crop rotation, i.e., not planting the same crop in the same place annually, can prevent the fungus from attacking the same species repeatedly, reducing the chances of infection【7†(Gardening Channel)】【13†(Epic Gardening)】.

Tool Sterilization

Sterilize your garden tools regularly with a solution of 1 part bleach to 9 parts water to avoid transferring fungal spores from one part of your garden to another【13†(Epic Gardening)】.

Pruning and Disposing Infected Foliage

Prompt removal of infected plants or plant parts and disposing of them properly (not in the compost) can help in managing the spread of the disease【13†(Epic Gardening)】.

Soil Management

Maintaining well-draining soil that is neither too soggy nor too dry is crucial. Fusarium Wilt thrives in overly wet or extremely dry soil conditions. Utilizing a moisture sensor to check the moisture level of the soil and ensuring it’s just right can go a long way in preventing Fusarium Wilt【13†(Epic Gardening)】.

The Path Ahead

Unfortunately, the battle against Fusarium Wilt is ongoing with no full-proof resistant varieties. However, by implementing these preventive measures, gardeners can significantly mitigate the risks and protect their beloved greens from this silent killer.

For more information on Fusarium Wilt and preventive measures, you may refer to the following resources: