Tomato rootstocks

[Dominic J]

Has anyone tried to grow them out and collected seed?

I haven't found much info on the subject. On other forums, I've seen a few mentions of people planning to do it, but then not posting the results. I found one mention with more details, I believe, about 'Maxifort' not giving a good tasting fruit at all.

All of these varieties are described as F1 hybrids. But then again, of course they are, why wouldn't they be described this way, even if it was true? It's a pretty strong disclaimer to dissuade seed saving, which would be otherwise tempting given the price of these seeds.

So my questions are on these subjects: If you've grown a rootstock to seed, what did it taste like, did the progeny suggest it was truly a hybrid or did it breed true, and if it did not breed true, how much variation was observed?

I intend to try this with 'Estamino' this year, and I'm curious to see if others have attempted it.

[William S.]

Some rootstocks are F1 habrochaites x domestic. That could be a really fun but frustrating project.

[Joseph Lofthouse]

I haven't grown Maxifort, but I understand it is derived from Solanum habrochaites, which is a green fruited species. Taste tends towards acrid and acidic. Solanum habrochaites are generally self-sterile, and any offspring are also self-sterile, therefore they are all F1 hybrids. If the variety is pure Solanum habrochaites,  it's very possible that they are true breeding F1 hybrids!!!! Gotta love the promiscuous tomatoes.

I've grown lots of interspecies hybrids between S habrochaites and domestic tomatoes. That's some fun growing, with huge diversity.

[Dominic J]

I just noticed there was a tomato subforum, whoops.

What's wrong with habrochaites? Are there fertility issues due to hybridization? Or is it because of self-sterility?

https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/nph.14130

This paper seems to suggest they can be all sorts of things, regarding fertility.

'Estamino' seems to have the most resistances of the bunch available (though it doesn't have them all). I figure there's nothing to lose by letting it bear fruit. If it breeds true, cheap rootstock seeds for the future. If it crosses out to my other varieties, then that's the start of yet another breeding project.

[Joseph Lofthouse]

The tomato forum has existed for a few minutes. No worries...

The versions of S habrochaites that I grow are 100% out-crossing. Nothing wrong with that, it's just different than the strategy used by domestic tomatoes.

If you grow Estamino, I recommend using at least 5 plants, to increase the odds that you get some plants that aren't closely related for cross-pollination.

[Dominic J]

Good info, thanks!

I'll think about it. On one hand, I would like a supply of true 'Estamino' seeds. On the other, maybe I wouldn't need to bother with grafting if I just cross it the other other varieties I'm growing, such as 'Mountain Magic' and 'Jasper'.

[William S.]

Should be interesting. I sure enjoy the interspecies hybrids. We have threads for that around here somewhere. Also on homegrown goodness.