Frequently Asked Questions

Jump To A Section

Getting Started Testing Collecting Samples Testing Process Shipping Samples Sample Analysis Symptoms and Treatment of Hop Latent Viroid Hop Latent Viroid – General Testing for Hop Latent Viroid Decontamination of Viroids Transmission of Hop Latent Viroid

Testing Questions

Getting Started Testing

Can I send my samples from another state?
Yes! TUMI Genomics sample collection process renders the plant material “unusable and unrecognizable” and is legally defined as agricultural waste.

The only plant tissue accepted in our testing laboratory is mature stalk. As indicated by the CSA, 21 U.S.C. § 802 (16) below, mature stalk is exempt from the definition of marijuana: “The term ‘marihuana’ means all parts of the plant Cannabis sativa L., whether growing or not; the seeds thereof; the resin extracted from any part of such plant; and every compound, manufacture, salt, derivative, mixture, or preparation of such plant, its seeds or resin. Such term does not include the mature stalks of such plant, fiber produced from such stalks, oil or cake made from the seeds of such plant, any other compound, manufacture, salt, derivative, mixture, or preparation of such mature stalks (except the resin extracted therefrom), fiber, oil, or cake, or the sterilized seed of such plant which is incapable of germination.”

In addition, our sample collection process involves grinding of stalk tissue with greater than 50% glass and plastic, rendering the material unusable and unrecognizable according to to waste disposal rules in Colorado and other states (see section 3-230, E1 – https://www.sos.state.co.us/CCR/GenerateRulePdf.do?ruleVersionId=9900). The material sent to TUMI Genomics is legally defined as agricultural waste. The sample is also mixed on-site with a strong detergent which irreversibly binds all oils in the sample rendering them unusable.
Can you test internationally?
How many tests do I need per plant?
How often should I test?

We recommend that you test your mother plants, which are the most important plants in your process, at least every six weeks for economically damaging pathogens. Screening a subset of clones via pooled testing is also important, especially if you are suffering, or have suffered, from an outbreak. Regular, consistent testing is critical to reduce economic exposure from pathogens and to protect your investment.
What do I test for?

What pathogens to test for depends on the type of cultivation facility you have (indoor, greenhouse, living soil, hydroponics, etc) and what kinds of symptoms you are seeing in your plants. The two most economically damaging pathogens in cannabis are hop latent viroid and fusarium, so we recommend screening for these two pathogens frequently; every six weeks is ideal. If you would like more information, see our testing panels here.
How long does it take to receive in the lab my sample tubes?
How long do the sample tubes last? How should I store the tubes?
Can I test more than one pathogen from the same sample?
How do I pay for testing?
Is there a discount in pricing for larger orders?

The Testing Process

When can I expect my results?

After our lab receives your samples, you’ll have a digital pdf of your results in 10 business days for the following tests: Water System Panel, Air Assay, and Growing Medium Panel.
How will I receive my results?
What information will be included in my report?
What testing method does TUMI Genomics use when processing samples?

For instructions on returning international samples, visit our website here: https://www.tumigenomics.com/submit-samples
How accurate are my results? Could there be false positives or false negatives? How sensitive is the test?
TUMI Genomics assays are validated by the same standards set by the USDA and are optimized to dramatically reduce false results. We use a specialized type of PCR called TaqMan PCR, which is more sensitive and accurate than normal PCR. Each test also includes an internal control that detects cannabis RNA, which allows us to determine the quality and integrity of your sample. We have conducted extensive validation on all our assays and you can find that data here. Of course, it is important to remember that no diagnostic test, regardless of design is 100% correct, 100% of the time.
How is the sample preserved until it arrives at the TUMI Genomics lab?

Each test includes an internal control that amplifies an RNA/DNA in all cannabis plants regardless of infection.
What happens if my sample fails?

We guarantee the success of your samples. If your samples fail for any reason, we will retest a new sample at no charge.
What if I have questions about my results?
What happens to my data?

All results obtained from TUMI Genomics are strictly confidential. Your data is stored in a secure database that is not accessible to anyone but the team at TUMI Genomics and only for the purposes of processing your results. We never share individual test results with any entity other than directly with the customer who shipped us the samples. Any further analysis of data to help us improve our testing process is anonymized and aggregated so your personal data is completely protected.

Collecting Samples

How should I sample my plant?
How much tissue do I include in the tube?
Will soil or other chemicals interfere with the test?
How do I track plant tissue samples for my tests?
Can I test my growing medium?
Can I test seeds?

Shipping Samples

Do I need to add ice packs to my shipment?
How long are the samples stable after I collect the tissue?
If I cannot ship the samples right away, should I store them in the fridge?
What carrier should I use to ship back my samples?

For instructions on returning international samples, visit our website here: https://www.tumigenomics.com/submit-samples
What address should I send my samples to?

I Have Results, Now What?

What do I do if my plants test positive?

If your plants test positive it is likely that you have a pathogen outbreak in your facility. The best course of action is to identify which plants are infected and remove them promptly. Diseased plants should be disposed of in a closed container and not composted. We can help you build a testing schedule specifically tailored to your results and facility size that will help you to quickly get the outbreak under control.
What do I do if my plants test negative?
What does it mean if my plant tested low-level positive?

A low-level positive result means that the PCR test detected the pathogen in the sample, but the level was very low. This result could indicate an early infection. However, because PCR is so sensitive, very low levels can also be caused by cross-contamination during sample collection. If a low-level result is detected for a critical variety, we suggest you isolate that plant and test again in a few weeks to confirm. Results that fall into the category are indicated in blue on your report.
What does it mean if my sample failed?

A failed sample means that the internal control, which looks for a part of the plant genome (a plant RNA), failed to amplify. Without robust amplification of the internal control we cannot be certain the integrity and concentration of the sample was sufficient to have been able to detect the infection. We rerun failed samples twice and guarantee that if your sample is not successful, we will run a new sample at no cost to you.
How can two samples from the same plant have different results?

Hop Latent Viroid Questions

Symptoms and Treatment of Hop Latent Viroid

What are the symptoms of hop latent viroid?

Hop latent viroid can have variable effects on infected plants. Plants can be stunted, grow slowly, display horizontal branching and brittle stems, leaf discoloration, and dramatically reduced flower size. Plants infected with hop latent viroid often show more severe symptoms when stressed. However, plants can also harbor asymptomatic infections that are still infectious, so the only way to be sure plants are free from hop latent viroid is by testing.
What causes the symptoms of hop latent viroid?
While there are a lot of theories as to the cause of symptoms due to viroids, the theory that has the most robust evidence is that viroids cause an auto-immune type response in the plant. The plant’s version of the secondary immune response (called RNA-interference) attempts to respond to the presence of the viroid, but this response backfires and the plant ends up attacking itself instead. If a critical component of the immune system (RNA-interference pathway) is removed, plants do not develop symptoms from viroid infections and if the immune system is artificially activated (without a viroid being present), plants mimic viroid-like symptoms.
How long does it take an infected plant to show symptoms? How long after infection until it will test positive?

The amount of time it takes for a plant to display symptoms depends on a lot of variables including plant age, plant size, the specific variety, and plant stress. Some plants don’t show severe symptoms until flowering. How long it takes an infected plant to build up enough viroid concentration to test positive, also depends a lot on plant size. For a small plant, 3 weeks is likely sufficient. However, in a very large mother plant, it can take months for the viroid to establish a systematic infection.
Is it true hop latent viroid can be in only some branches and not others?

Yes, hop latent viroid can exist at variable levels around the plant. The reason for this phenomenon is due to the way viroids travel through the plant. Viroids are dependent on the movement of sap through the vascular system to gain access to the entire plant. Viroids will accumulate in areas sap is moving into (such as active growth), but to a lesser extent in areas where sap is moving away (such as old growth). This movement pattern occurs at the time of infection, meaning new growth when the plant was infected is likely older growth on the same plant several months later. Because the timing of infection is likely unknown, it is difficult to predict which branches contain high levels of viroid and which do not.
Is there a treatment for hop latent viroid?
There is no topical treatment for viroids. You cannot cure a plant using a spray or by dipping a clone in a solution. Meristem tissue culture can remove viroids from a critical variety, but the process is time consuming and can be costly. The best way to treat hop latent viroid is to prevent it from entering and spreading in your facility through sanitation and regular testing.
How is the sample preserved until it arrives at the TUMI Genomics lab?

Each test includes an internal control that amplifies an RNA/DNA in all cannabis plants regardless of infection.
What happens if my sample fails?

We guarantee the success of your samples. If your samples fail for any reason, we will retest a new sample at no charge.
What if I have questions about my results?
What happens to my data?

All results obtained from TUMI Genomics are strictly confidential. Your data is stored in a secure database that is not accessible to anyone but the team at TUMI Genomics and only for the purposes of processing your results. We never share individual test results with any entity other than directly with the customer who shipped us the samples. Any further analysis of data to help us improve our testing process is anonymized and aggregated so your personal data is completely protected.

Decontamination of Viroids

How long is hop latent viroid stable on surfaces?
How do I remove viroid contamination?
How do I sterilize my tools to prevent spread of hop latent viroid?

Viroid contamination on tools can be removed using 10% bleach with a contact time of one minute or more. We recommend trimming plants with multiple pairs of scissors in a jar of 10% bleach. When you move from one plant to another, drop the dirty scissors in the bleach solution and take a fresh pair from the bleach jar. Rotate to a pair of scissors that have been in the bleach for a minute or more when you move to the next plant. The bleach solution should be replaced if saturated with plant material.
What type of bleach should I buy?

The active ingredient in bleach that destroys viroid contamination is sodium hypochlorite. Confirm the concentration in the commercial bleach you purchase is >6% (most are between 5.25% to 8.5%). Many splash-less bleach solutions fall below this concentration so be sure to confirm the sodium hypochlorite concentration. Calcium hypochlorite has the same mechanism of action as sodium hypochlorite and is an acceptable substitute.

For instructions on returning international samples, visit our website here: https://www.tumigenomics.com/submit-samples
How do I make a 10% bleach solution?
How long can I use a diluted bleach solution?
Can I use alcohol to clean my tools?

While alcohol can be effective to sterilize against many pathogens, it is NOT effective at removing viroid contamination. Alcohol actually stabilizes viroids, which increases the rate of transmission between plants. Bleach can leave a salt residue after drying and alcohol can be used to remove this residue. However, care should be taken to NOT mix liquid bleach and alcohol, as this makes a toxic gas (chloroform). Alcohol can also be used to remove plant matter before bleaching as long as a bleach step is included after.
Is heat sterilization effective at removing hop latent viroid?
Heat sterilization is not completely effective at deactivating viroids. Experiments have shown that a propane blow torch or extended heating in an oven does not guarantee viroid decontamination. Heat should not be the only method of viroid sterilization that is used, especially on contaminated cutting tools.

Hop Latent Viroid - General

What is hop latent viroid?

Hop latent viroid (HLVd) is a miniature molecular parasite that is pathogenic (i.e. causes disease) in cannabis and hops plants. HLVd is composed of a single circular, highly structured RNA that replicates by hijacking the molecular machine that normally interprets the plant’s DNA (RNA polymerase II) and forces that machine to copy the viroid instead.
How is a viroid different from other pathogens?

There are many different types of pathogens that cause disease in cannabis plants including fungi, oomycetes (fungus-like), viruses, and bacteria. While these pathogens have distinct biology, one feature they share is that the genetic information of these pathogens is protected by outside coat. This coat, composed of fat, carbohydrates, proteins or all three, is essential for the pathogen’s survival. Viroids, on the other hand, do not have an outside coat. They are literally an unprotected, free-floating piece of genetic material. What this means is that disinfectants that work by breaking up fats or proteins (i.e. soap, alcohol, etc) do not work to destroy viroids.
Where did hop latent viroid come from?
How prevalent is hop latent viroid?

Hop latent viroid is prevalent in hops plants worldwide. However, there is no published data describing the geographical distribution of hop latent viroid in cannabis. At TUMI Genomics we have conducted more than 18,000 PCR tests and have identified HLVd in almost every state in the USA, including Alaska and Hawaii, and impacts 73% of the cultivation facilities. We have also characterized infections in Canada and the United Kingdom. Based on this data and the wide geographical spread in hops plants, hop latent viroid is very likely a global cannabis pandemic.
Can hop latent viroid infect other plants besides cannabis?
What is the impact of hop latent viroid on the Industry?

Testing for Hop Latent Viroid

My plants look fine, should I test for hop latent viroid?
How do I test for hop latent viroid and How often should I test?
How important is viroid load in my results? Should I destroy a low-level HLVd positive plant?

Viroid load estimates the amount of viroid in your sample. This number can help you understand the severity of a potential infection. However, the significance of a low-level viroid infection is not clear. There is no cure for viroids in any agriculture crop besides tissue culture nor evidence that a sick plant can recover or “heal” itself. The normal mechanism that plants use to combat viral infections (RNA-interference) is not efficient on viroids. Because of this, the safest route is to treat low-level infections as potential sources of spread and isolate or remove those plants.

Transmission of Hop Latent Viroid

How is hop latent viroid transmitted? (can it spread through touching or through the air?)
Can insects transmit hop latent viroid?
Is hop latent viroid transmitted in seeds?
Can hop latent viroid be transmitted on my clothes or on my hands?

Hop latent viroid can remain infectious on cotton and leather for 24 hours or more and about 3 hours on human skin. We strongly recommend individuals touching plants wear personal protective clothing and gloves. While trimming, gloves should be sterilized between each plant using 10% bleach. The bleach can be placed in a spray bottle and used on gloved hands similar to hand sanitizer. There is no need to rinse the bleach off the gloves before moving to the next plant.
If a positive plant comes in contact or is in the same space as other plants, does that mean all the plants now have hop latent viroid?

In order for hop latent viroid to spread infected sap must gain contact with a wound in another plant. If the rubbing between two plants resulted in damage or micro-tears, it is possible that the viroid could spread. However, two plants simply sharing the same physical space does not guarantee transmission. Shared water could transmit viroids between sick and healthy plants, so care should be taken to avoid shared water between plants of unknown infection status.

An abstract design featuring interconnected shapes, including circles and hexagons, in a blue outline on a black background. The arrangement gives a complex, network-like appearance.