HLVd is difficult to detect, making molecular testing essential in preventing considerable financial losses for growers. Don't allow HLVd to catch you off-guard – consider partnering with a trustworthy laboratory to preemptively combat this
Below are the key take-aways about HLVd and the implications to consider applicable to your operation
- The "duds" disease, caused by the hop latent viroid (HLVd), has emerged as a significant threat to the cannabis industry in North America since its first detection in 2019 
- HLVd infection can cause a 50%-70% reduction in the tetrahydrocannabinol (THC) content of the crops, significantly diminishing their commercial value 
- HLVd is one of the smallest known infectious agents, and despite not showing characteristic symptoms, induces physiological changes in plants that affect the metabolites involved in terpene production, with linalol, myrcene, α and β-pinene reduction ranging from 13 to 41% 
- Symptoms include stunted growth, smaller leaves, malformations, and reduced flower mass, resulting in up to a 50% reduction in cannabinoid and terpene production. 
- As of 2021, 90% of all cannabis-growing facilities in California tested positive for HLVd 
- Primary method of control is by using uninfected materials 
- The best detection method is through qPCR testing of the plant's genetic material 
- Remember the VITAL signs and symptoms of the HLVd
Don't allow HLVd to catch you off-guard – consider partnering with a trustworthy laboratory to preemptively combat this silent assassin. Email, call or text Abraxas Labs to learn more and be ahead of the game in protecting your crop!
Table of Contents
- HLVd Introduction
- Pneumonic To Remember
- How is (HLVd) spread controlled?
- Detection and Management of HLVd Infection
- How can Hop Latent Viroid be controlled?
- Final Thoughts
What is Hop latent viroid (HLVd)?
Are you a cannabis cultivator or processor dealing with the silent enemy, Hop Latent Viroid (HLVd)? It is a little-known viroid that quietly infiltrates cannabis plants and can significantly dent your yield and overall revenue. HLVd's sly, difficult-to-detect nature makes molecular testing essential in preventing considerable financial losses for growers. Although plants with HLVd may not show any symptoms, those that do will normally have a lower yield of cannabinoids, reduced terpene content and reduced overall yield. This can cause a significant financial loss for growers, which is why it's becoming increasingly important for cannabis operators to test for HLVd early on. Don't let HLVd sneak up on you! Make sure to entrust your samples to a reputable laboratory and detect HLVd before it causes any damage.
At Abraxas Labs, we've created an easy-to-remember acronym, VITAL, to help you remember the key facts about an HLVd infection:
- Viroid structure
- Impacts on yield and quality
- THC content reduction
- Acid and aroma alterations
- Latency and prevalence
Let's take a closer look at these areas:
- Viroid structure: HLVd is a small, RNA molecule. It is similar to viroids and is classified under the genus Cocadviroid 
Impacts on yield and quality: HLVd significantly reduces hop yield and quality, leading to economic implications. Yield losses can range from 8% to 37.5%. In cannabis, HLVd infection can cause up to $4 billion in annual losses 
THC content reduction: In cannabis plants, HLVd infection can cause a 50%-70% reduction in THC content, significantly reducing commercial value .
Acid and aroma alterations: HLVd infection reduces α-bitter acid content and increases β-bitter acid content, leading to early hop cone maturation. Changes in α-bitter acid, β-bitter acid, oil content, and terpene profile can affect the aroma of your product. This is also true for terpene content (see discussion below)
Latency and prevalence: HLVd doesn't typically show visible disease symptoms, hence the name "latent". Despite this, it is widespread, with a 90%-100% prevalence in European hop germplasms and an estimated 90% prevalence in California's cannabis-growing facilities.
How is (HLVd) spread controlled?
Detection and Management of HLVd Infection
Tip: if you are collecting samples to bring to Abraxas Labs for testing, make sure to collect plant material from upper and lower parts of the plant
How can Hop Latent Viroid Infection be controlled?
HLVd can be eliminated from cannabis or hemp plants via tissue culture, but it is a lengthy and laborious process. As with most plant pathogens, prevention is key. The use of proper sanitation practices will go a long way in preventing the spread of HLVd and other plant pathogens. Handle plants with fresh gloves every time, and sterilize tools regularly. Before entering the growing area, visitors and staff should use footbaths and wear hairnets, beard nets, gloves, and coveralls. Before taking cuttings, cultivators should test mother plants for viroid infection with qPCR assays. To avoid introducing infected plants to their growing environment, cultivators should also screen incoming clones with qPCR assays. Additionally, more research is currently underway regarding the possibility that some cannabis cultivars may be resistant to the viroid and therefore, are good candidates for breeding and cloning since they may help prevent the plants from ever becoming symptomatic.
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