What growers should know about Hop Latent Viroid

For many years, growers and breeders have speculated why “dud plants” are seen across different cannabis crops.

Cannabis has faced many viral infections. Due to viruses and viroids, some varieties mutated into genetic changes over time, altering the evolution of the plant. But how can we detect Hop Latent Viroid (HLVd)?

Viroid vs. virus: what’s the difference?

Hop Latent Viroid (commonly known as Dudding Disease) is a single-stranded, circular infectious RNA. It is not a virus. Let us explain the difference:

Viroids only replicate in plants, and viruses are more complex than viroids. Viroids are composed of only RNA, while viruses are composed of a protein capsule enveloping their genetic material.

Viruses infect new hosts only once they enter a host and replicate within it. Viroids are transmitted through direct contact of a healthy plant with an infected one, and can also be transmitted by contaminated tools and instruments (gloves, scissors, tweezers, even human hands).

Because HLVd is latent, there are many asymptomatic transmissions. It can spread without symptoms — and you’ll only realize it when it is too late.

HLVd symptoms

Hop Latent Viroid is a silent viroid, meaning it may or may not show early visual clues from its presence. Some physical symptoms in cannabis plants include stunting, smaller and malformed leaves, yellowing, and reduced trichome production.

What about transmission?

HLVd and other viroids in your garden or greenhouse can spread quickly from infected to healthy plants. The main transmission causes are:

• Infected equipment: sterilize equipment before working on new plants to reduce the possibility of contamination.
• Clones: before cutting, we recommend a complete pathogen test to avoid infected clones.
• Seeds: currently under research, but HLVd has roughly an 8% chance of being present in the seeds of an infected mother plant.
• Human touch: managers and staff must sterilize hands and gloves before moving from one plant to another. A simple touch is enough to transmit HLVd.
• Bugs and pests: pests are always present, and their bites may transmit HLVd, spreading the pathogen through your entire garden in a blink.

A simple touch is enough to transmit HLVd.

How can you prevent HLVd?

Here are some essential tips:

• Keep your equipment clean. You can read more about how to sterilize your tools on our Instagram profile.
• Keep pests under control.
• Tissue culture: HLVd can travel through the plant’s vascular system and may be left behind in older tissues as plants develop. You can outgrow the problem by producing clones from the infected plant — the more cuttings a grower roots, the higher the chances of selecting a clean one.
• Pay special attention to visitors: HLVd may arrive on a visitor’s hand, glove, or even shoes.
• Screen incoming material: when a plant or leaf enters, don’t accept it unless it has a negative DNA HLVd test. It’s the only way to be sure it isn’t a threat to your garden.

Thank you for reading! We hope you find this information useful. If you have any doubts, don’t hesitate to ask us about any related topic.