Is Fire blight or virus susceptibility worse in a rootstock? Which one?

If I have to choose between a rootstock that needs virus free scions or has fire blight susceptibility, which should choose? I don’t see how I could ever guarantee a virus free scion, but can I treat blight?

My tomatoes usually get blight if it rains a lot, but they’re closer to the ground. I figured apple trees in my area might suffer from blight as well. I don’t know of anyone in my area to ask, so I’m guessing.

But virus free scion wood? Sounds hard to verify and no way to fix it or help fight adverse effects.

I’m in 7b with more wet than usual weather. Looking for dwarf rootstock for trellising. I can’t tell what to get now. Geneva looked good except for the virus free scion wood. About 25 trees probably.,

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With Geneva rootstocks many are not susceptible to latent viruses. You don’t have to have virus free scionwood with them. See this chart for some options. The chart tells you which rootstocks are susceptible and which are not.

I would suggest G11 or if you want a bit more vigor G214. G41 can have problems with weak graft unions I would avoid it unless you’re planting in an area sheltered from wind and the tree will be well supported.

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Some tangential questions…what happens when a virus gets introduced to a tree?

AFAIK virus is something much smaller than bacteria and fungi. Humans get viruses all the time, and in some cases it causes dna of the host to change as virus gets embedded into the genome of the host.

It sounds like when a tree gets a virus, it’s a done deal and there’s no way to get rid of the virus. I’ve also heard of also eliminating viruses from rootstocks, how is this accomplished? Through breeding it out? Intriguing but also confusing.

By tissue culture propagation; the meristem is virus-free even if the mother plant is infected.
There are also other methods (“therapies”).

I see, thanks.

I’m not sure how rare viruses are, but many viruses are listed to be spread by grafting (which obviously wouldn’t happen naturally). In a more natural setting, I would think trees are used to defending against viral vectors and trees with poor defenses get culled by mother mature. But nothing about growing cultivars of same clonal trees is really natural, so in the end fruit trees have much greater vulnerability to viruses and other disease.

Being in humid area, I would rather have fire blight resistance. If the tree is vulnerable to virus and I did introduce a virus to the tree, I’d rather have the viral tree die before spreading the virus to others.

Some other resources also:

I’ve heard of G.16 being used as a “canary” for detecting viral infection without paying for lab work due to its extreme susceptibility.