As the name suggests, Hop Latent Viroid is a virus visible in Humulus lupus (Hop). Initially, it was believed that this viroid (an infectious structure made of nucleic acids affecting plant growth) did not produce any disease symptoms and led to the term “latent” being incorporated into the viroid name.

Research has shown that HpLVd emerged in plant species other than hops; due to the increase of indoor cultivation and vertical farming operations in the UK. And as a result of imported cuttings becoming more popular as a source of phenotypes with growers.

How do you know if your plants are infected with HpLVd?

Symptoms of HpLVd include smaller plant size compared with healthy plants, up to 30-50% decreased plant yield and malformed leaves. The stems of a plant infected with HpLVd are relatively easy to break and usually detected when the plants are trained during the vegetative stages.

How is HPLVD spread?

Research suggests that the plant virus can be passed on when cuttings are taken from infected mother plants; at the same time as taking cuttings from healthy plants. Sap from an infected plant can easily be transferred via tools to healthy plants during pruning and thinning. During seed production, plants have tested positive for the viroid, through the cross-breeding of HpLVd-affected genetic lines.

How can you prevent HPLVD?

  • Ensure that all scissors and trimming tools are thoroughly sterilised before moving on to another plant to avoid the risk of cross-contamination
  • If you are buying genetic imports, ask breeders and distributors whether their seeds have been tested for HpLVd
  • Clean and sterilise your grow tent regularly

What can I do if I have an HPLVD infection?

If you are concerned that you have bought infected cuttings. Remove them from your grow room and destroy the plants. DO NOT TAKE CUTTINGS. In studies, the most effective treatment agent against HpLVd was bleach; however, it isn’t recommended to run a bleach solution through your hydroponics system, as this could negatively affect your plants. ALIEN® has manufactured a sterilising solution, RootRotX™, as effective as bleach and is entirely safe for your plants. For best results, run RootRotX™ every 7-10 days, through your hydroponic system, and regularly clean grow room walls and floors.