How You call this in English

This is my Prunnus, How You call or the name of this pests or disease.
What products Do You use
Many Thanks Alejandro

Looks like it could be a root gall to me. Look at this and see if you agree http://ucce.ucdavis.edu/files/repository/calag/img6203p111.jpg
If it is soft and spongy, it fits the description here. http://ucanr.org/repository/CAO/landingpage.cfm?article=ca.v062n03p111&fulltext=yes

A biological control agent is mentioned in the text, but I have no experience of this.

Your tree has a crown gall. It is usually caused by an infection. I never heard of any control. You should dispose of the tree, probably burn it, before any of your other bonsai get infected.
Iris

Thanks to all, yes is crown gall.
Best regards Alejandro

Try slicing off the gall and treating the area with lime sulpur. The old remedy was to use Bordeaux mixture. This definitely works in treating crown gall on quince.

Regards
Peter Adams

There is a good reason to keep tools and hands sanitized when working with woody specimens. You don't want to cross infect your trees with a microorganism like crown gall.

You can cosmetically remove the gall, but the tree remains infected. Treating the wound with solvents doesn't really cure a bacterial infection that has genetically altered the tree. Treatment may keep the gall stage in remission but the tree and soil will remain infected and place your other trees at risk. Maybe if you isolate the infected tree and keep all tools and hands sanitized, you might prevent cross contamination when working with your other trees. However, the infection can also spread by bugs that aren't privy to our sanitation etiquette.

Best regards from an original IBC member,
Geoline

Also rain splatter can spread it. MY recommendation would be to dispose of the tree and soil in some distant location -- and NOT in a compost pile.

Geoline wrote:
Best regards from an original IBC member,
Geoline

Glad to have you here. I've been wondering if you were still around.
Iris