Hop Latent Viroid Infection in Cannabis: Consequences, Detection, and Mitigation

Hop latent viroid (HLVd) infection lowers the commercial value of cannabis by reducing flower harvest weight, THC concentration, and terpene production. Unlike other microbial contaminants including yeast, mold, and pathogenic bacteria, HLVd is not subject to regulatory compliance testing due to the absence of known human safety concerns. However, because of the financial losses associated with HLVd infection, cannabis cultivators are advised to adopt a tiered approach to safeguard against HLVd and other microbial contaminants to reduce the risk or spread of infection. These strategies include implementing (in order of increasing complexity and effort): basic biosecurity standard operating procedures, non-burdensome environmental monitoring plans (EMP) and rational Hazard Analysis and Control Point (HACCP) plans. Remarkably, these strategies not only shield against HLVd but also confer enhanced protection against other financially detrimental microbial contaminants such as yeast, mold, and pathogenic bacteria. Consequently, the adoption of these protective measures yields additional benefits, including the production of a higher quality cannabis product that commands premium pricing, a reduction in microbial contaminant test failures without reliance on a kill-step, and the fulfillment of a crucial element for future Good Manufacturing Practices (GMP) certification.

Learning Objectives:

1. Review HLVd properties and the biological effects of infection in cannabis.

2. Describe methods of HLVd is detection and its modes of transmission.

3. Outline HLVd biosecurity planning and infection mitigation actions.