Can Tissue Culture Remove Hop Latent Viroid (HLVd)?
Professor DeBacco

Testing/Screening is Still Needed
This is still an important part of the process.
By testing plants that are infected can be culled out as even tissue culture does not ensure a clean plant.
However, culturing from a clean plant and producing known clean plants is a method that can lead to a “clean” facility.
*Testing/screening should still occur, if you have employees, bring other plant material in, plan on keeping a plant as a mother and to know you do (still) have a clean facility.

Is Tissue Culture the Answer?
Based on hops it is possible to get clean tissue and eliminate the passage of the viroid to the new tissue.
Portion of the plant the sample is taken and cultivar being used for the plant cells all have an impact on the effectiveness of this process.
However, when multiple rounds are done with testing (screening) in-between it is possible to rid a line of the viroid.

Meristem Culture preferred
With tissue culture you only need a small number of initial cells, so where should you take them from?
Meristem culture is more advantageous compared to using material from a node.
Remember that the viral load can vary in a plant
Some people think this is because the plant grows quicker than the viroid can spread and this may be true to an extent, but in reality the viroid is not far away.

Common Locations based on Tomatoes
When inoculated it is more likely to be found above (rather than below) the point of intentional infection
(At least initially)
It is very common in roots and this may be where it initially concentrates.

Look to the Potato
Potatoes are vegetatively propagated
These are often grown in tissue culture to produce virus free plant stock that will be used for a number of years and then the tissue culture process is repeated to help ensure clean tissue.

Why Meristem Regions?
The very tip of the plant is the new fastest growing cells that may be able to out pace the growth/spread of the virus.
This is not a guarantee, but it does help potentially increase the odds of generating virod free tissue.

Link to Lecture Slides: https://drive.google.com/file/d/1nAJP...

*Due to the description character limit the full work cited for "Can Tissue Culture Remove Hop Latent Viroid (HLVd)" can be viewed at... https://docs.google.com/document/d/15...