Cannabis Cultivation: How to Choose A Lab for Accurate Pathogen Testing

Explore the key factors growers should consider when selecting a testing service and the direct impact these decisions can have on cultivation success.

As cannabis growers, it’s essential to stay ahead of crop-threatening pathogens. Fungal pathogens, among other threats, can severely impact crop health and yield. 

But what does this mean for cannabis growers? Let’s dive deeper into what you should consider when selecting a laboratory for cannabis pathogen testing and how this can directly affect your cultivation practices.

Selecting the Right Laboratory for Pathogen Testing

Choosing the right laboratory is not just about getting results—it's about ensuring those results are accurate, actionable, and relevant to your unique cultivation environment. Below, we explore key factors that cannabis cultivators should prioritize when selecting a lab.

1. Assay Suitability for High Complexity Labs

Imagine you're running a large-scale indoor cultivation operation, and powdery mildew has become a recurring problem. You decide to send samples to a lab for pathogen testing. The lab uses LAMP assays, which can be useful in some settings but might not offer the precision needed for a high-stakes environment like yours. Instead, find a lab that uses PCR assays that provide more precise and reliable results, ensuring that you’re not taking unnecessary risks with your crop.

BONUS: Labs offering PCR testing can also help quickly identify the pathogen's exact strain to determine the most effective treatment.

Looking for more information about the difference between LAMP and PCR methods? Read our blog about various detection methods used in cannabis pathogen testing.

2. Comprehensive Validation Documents

You wouldn’t buy a car without knowing its safety ratings or fuel efficiency. Similarly, you shouldn’t rely on a lab that doesn’t provide comprehensive validation documents. These documents are your assurance that the lab’s assays are sensitive, specific, and inclusive of the pathogens most relevant to cannabis cultivation.

BONUS: Testing with a lab that has rigorous validation standards can identify early, low-level infections. Catching these infections early allows you to prevent THC content loss and maintain the potency of your cannabis, ensuring higher-quality yields.

You can find TUMI Genomics' validation documents here.

3. Justified Sample Collection Protocols

The tissue sample you collect can drastically influence the results of pathogen testing. A well-informed lab will justify its sample collection protocols based on pathogen biology. For instance, testing for Fusarium—a soil-borne pathogen—might require root samples rather than just leaves or stems.

BONUS: Using root tissue for cannabis pathogen testing, specifically for HLVd, has been proven to be the most predictive and reliable tissue for accurate results. This approach also preserves the plant's valuable leaves, allowing you to maintain optimal growth and yield without sacrificing essential foliage.

4. Sample Integrity During Shipment

Pathogen testing accuracy hinges on the integrity of your samples from the moment they leave your facility to when they arrive at the lab. For instance, a sample that isn’t properly preserved during shipment could degrade, leading to false negatives or positives.

To prevent this, plant tissue samples can be preserved using temperature related methods, or a solution that places the sample in temporary stasis. Choosing the right preservation method ensures the sample's stability, ultimately providing more accurate and reliable pathogen testing results.

BONUS: Sample collection methods that don’t require set temperatures can prevent sample degradation even if packages are delayed.

5. Source and Efficacy of Controls

Positive and negative controls are crucial to verify that the entire testing process, from sample preparation to final results, is functioning correctly. Ask your lab about the source of their control materials and how they ensure these controls test the efficacy of every step.

BONUS: Using internal controls reduces the risk of false negative and false positive results, which have been shown to range between 17% and 30% annually when testing five of the major crops (maize, rice, wheat, potatoes, and soybean) for pathogens and pests at a global level (1, 2).

6. Accuracy and Transparency

No lab can guarantee 100% accuracy, and any lab that claims never to produce false positives or negatives should be approached with caution. Transparency about limitations and potential errors is crucial for building a trustworthy partnership.

BONUS:  A lab that stands by their science will often process, or rerun, samples at no cost to the grower. 

 7. Pathogen Understanding

A deep understanding of the pathogens affecting cannabis is essential for accurate testing and effective management. For instance, a combo test for Hop Latent Viroid (HLVd) and Lettuce Chlorosis Virus (LCV) should be justified with an understanding of why these pathogens are tested together and their symptoms in cannabis crops - especially because one of these pathogens is a viroid and the other a virus. 

BONUS: Combination tests are not necessarily less accurate than single-pathogen tests, and can sometimes be more affordable. But ask your lab for clarification about their testing procedure for the different pathogens. 

Advocate for Your Plants

By choosing a laboratory that excels in these areas, cannabis cultivators can significantly mitigate risks and ensure their pathogen testing processes are robust and reliable. Accurate and reliable pathogen testing is essential for maintaining crop quality, optimizing yields, and achieving consistent and efficient cultivation practices. 

At TUMI Genomics, we are committed to providing superior pathogen diagnostic services to support cannabis cultivators in preventing and managing pathogen-related challenges. Connect with our team for more information on our services and how we can assist you in your cultivation efforts.

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About TUMI Genomics

TUMI Genomics is advancing cannabis cultivation by bringing biological insights to help commercial growers thrive. Through comprehensive preventative solutions, superior pathogen diagnostics, and AI-driven insights, TUMI Genomics is helping cultivators start clean and stay clean. The unrivaled diagnostics, transparent validation and industry-leading pathogen detection innovations provided by TUMI Genomics are raising the standards of commercial cannabis cultivation. The team at TUMI Genomics is composed of deeply experienced Ph.D. molecular biologists, bioinformaticians, business strategists, and accomplished serial entrepreneurs.

Media Contact: Hailey Spencer, Marketing Director

hailey@tumigenomics.com

Research Inquiries: Tassa Saldi, Ph.D., Co-Founder and CSO

tassa@tumigenomics.com