TUMI Genomics released a new study that identifies root tissue as the most trustworthy tissue type for accurately detecting Hop Latent Viroid (HLVd) infection in cannabis plants. The study, done in partnership with Kaprikorn Nurseries, used samples from distinct locations of plants identified as infected with HLVd.
Hop Latent Viroid is a tiny pathogenic agent that has been shown to be the molecular cause of "dudding disease" in cannabis plants. Because of the negative impact of this pathogen on cannabis flower, Hop Latent Viroid is causing major economic losses in the industry. Estimates indicate that upwards of 4 billion dollars of market value is lost each year to this pathogen alone.
To determine variability in viroid amounts throughout cannabis plants, the study used twenty-five individual samples taken from distinct locations around each plant used in this research. Tissue types sampled included: petiole samples from older growth, petiole samples from newer growth, stem samples from freshly cut upper clones, upper root mass samples, and lower root mass samples.
Samples were processed at the TUMI Genomics Laboratory using TUMI's proprietary triplex TaqMan qRT-PCR assay, a test with a limit of detection (i.e., the viroid level at which the PCR test is 95% accurate) of 7.5 viroid copies per reaction. This assay is considered one of the most sensitive and highly specific HLVd tests in the market and one of the few with published validation.
Dr. Tassa Saldi
Dr. Tassa Saldi, PhD, co-founder and Chief Science Officer at TUMI Genomics, noted, "The data indicates that the top root tissue of infected cannabis plants contains the highest viroid load and consistently displays the presence of HLVd genetic material. This strongly suggests that HLVd tests done without including root tissue have a high chance of missing infections, putting your facility at serious risk for major losses due to Hop Latent Viroid. It is still ideal for getting several tissue samples from different locations throughout the plant for accurate diagnostic testing. Multiple tissue sampling is recommended to make sure that diagnostic assays detect HLVd in the submitted tissue even if the infection is early or not broadly distributed".
Mia Nelson, co-owner of Kaprikorn Nurseries, commented, "After 3+ years running over 10,000 tests with five different labs, we've learned some things the hard way. Before picking a lab, ask questions. What are their detection limits? Do they have an internal quality control to ensure the test worked properly? How do they prevent sample degradation? Do they have a fact-based rationale for when and where to test? Then compare all your options before making a decision. Your lab partner can make or break your business".
For more information:
TUMI Genetics 
www.tumigenomics.com