What is HLVd?

Hop Latent Viroid is an infectious RNA pathogen that was noted in 2017 by multiple cannabis cultivators in California. Disease symptoms include stunting, chlorosis of leaves, and reduction in yield. HLV has the potential to greatly reduce quality and quantity of the plant. Plants may grow shorter with smaller leaves and tighter node spacing. Once flowering, infected plants will have smaller buds with fewer trichomes.

What is CCV?

Cannabis Cryptic Virus is a double stranded RNA virus that may interact with other fungal infections causing symptoms in cannabis plants. Furthermore, CCV can be vertically transmitted through seeds, which means breeders may want to screen plants before crossing.

What is LCV?

Commonly found in lettuce plants grown in Southern California, LCV is thought to have a wider host range which includes cannabis and hemp. Infected plants may show stunted growth but may not show obvious signs of disease until a few weeks into flowering. Visual signs include yellow, rolling, brittle leaves. Although the infection won’t kill the plant, the yield will be greatly reduced. Infected plants will produce smaller flowers with fewer trichomes, cannabinoids, and terpenes.

Infected plants may show up to a 90% reduction in cannabinoid and other phytochemical production.

A simple leaf test!

Prevention is key – Screening incoming clones and using proper sterilization techniques is the most effective way to keep HLVd, CCV and LCV disease outbreaks at bay.

The most accurate diagnosis will be achieved by testing a plant in triplicate. Leaf hole punches are taken from the the top, middle and bottom of the plant. Samples in each area should be taken from the oldest leafs, as they will have the highest viral load.

– Use a 10% bleach/water solution
– Isopropanol does NOT kill HLVd
– In addition to dipping, also wipe tools clean
– Quarantine potentially infected plants
– Test all incoming clones
– Periodically test your rooms

Don’t take a chance. Test all incoming plant materials and include periodic screens in your standard operating procedures.

Estimated $4 billion Industry Wide Loss

See the report from Dark Heart Nursery