I have grown better boy for many years with great results. I simply purchase plants every spring since I don't have the patience to grow from seed. This spring, I planted my better boys, and decided to allow some of the seed sprouting from tomatoes which dropped last year to continue growing. Since I don't totally understand the F1, F2, F3, and "growing true" terms, what should I expect to be produced from the seeds from last years better boy tomatoes? Should I expect one of the parent plants of the better boy hybrid to be the result of last years seed?

*****

What you now have are F2 volunteer plants from the original F1 Better Boy. The F1 seeds from last years fruits fell to the ground and those seeds were then F2 seeds that then gave rise to your now F2 plants.

Depending on how many plants you have you could see red fruited or pink fruited plants. But in no case will those be the same as either parent since what's happening is that the genes in the original F1 are now segregating out, meaning that they're being put in different combinations in different plants.

That's not to say that those F2 plants might not be very good plants with good fruits.

I had started on dehybridizing Big Boy F1 and initially put out 12 F2 plants from saved seed and got two that were pink fruited ( from Teddy Jones) and 8 that were red.

Dr. Schifriss, who bred Big Boy, told me I couldn't get out more than about 80% of the genes for Teddy Jones, and that's what I was going for, and the same would be true for the red parent of Big Boy.

And since Better Boy F1 is also a cross between Teddy Jones and a red parent, I would assume you'd see roughly what I did when I set out my 12 plants from F2 saved seeds saved from the F1 fruits of Big Boy.

So you might be nicely surprised, but you aren't going to get back either parent with all the genes they had in the beginning.

Below I've linked to an excellent website which explains what happens with saved seed and a lot more. It's the website of mulio, aka Keith Mueller, who often posts here. So if you want to know more about the genetics involved just click on the word Culture on the home page and then look at the three links at the bottom of that page.

And there's a lot more information at the whole site for anyone interested.

Hope that helps.

Carolyn

Here is a link that might be useful: Some Tomato Genetics

Great website, Carolyn! Even I can understand most of it, although I need to read it again. I have been experimenting with Brandyboy and Big Mama on a very amature basis. I'm up to F6 Brandyboys and they are still just like the F1s - still all PL. The Big Mamas are up to F3 and also still true. It's been an interesting experiment.
John A

If i rememebr right, PL is recessive so the parentage of Brandy Boys is PL. So shouldn't you always get PL? Their might be other changes you notice though

If i rememebr right, PL is recessive so the parentage of Brandy Boys is PL. So shouldn't you always get PL? Their might be other changes you notice though

****

Yes, PL is recessive to RL but if two varieties heterozygous for leaf form, which would make them then RL, are crossed then one could get a PL selection.

Cc X Cc would give you on average 1/4 plants that was cc, which is PL.

I know of others who have tried to dehybridize Brandy Boy and have gotten mixed results as to leaf form and fruit shape and size and even fruit color, b'c two folks I know of got red fruits.

What you see is really dependent on how many F2 plants are put out, what selections are made from those and then how many F3 plants are put out, etc.

Carolyn

My sample size is small. I probably had 6 F2s and 6 F3s, but only 3 F5s.
John A

Carolyn,
Given the opportunity, I want to display my total ignorance of plant genetics by asking a few questions.

1. If all tomato plants are members of the nightshade family, does that mean that a mutation occured to a nightshade plant in the distant past that resulted in the genetic parent of all tomato plants?

2. If the answer to the previous question is yes, or partially yes; does that then mean that all subsequent non hybridized tomato vareities are the result of mutation and cross breeding of mutated plants.

3. Can a plant be reverse bred to "dehybridize" it? Can you know without examining and comparing the genome of the plants?

4. Can a hybrid plant be bred through successive generations which will result in a hybrid which will always breed true in the future?

Thanks

Ted

1. If all tomato plants are members of the nightshade family, does that mean that a mutation occured to a nightshade plant in the distant past that resulted in the genetic parent of all tomato plants?

The nightshade family, Solanaceae, is very large and has over 100 different genera that includes not just tomatoes, but eggplant, pepper, potato, petunia, shrubs of all kinds and lots of other flowers.

They all evolved differently, so no, a single mutation in one member of the Solanaceae family did not give rise to tomatoes.

2. If the answer to the previous question is yes, or partially yes; does that then mean that all subsequent non hybridized tomato vareities are the result of mutation and cross breeding of mutated plants.

The answer above was no, but of all the OP ( open pollinated) varieties we know, they first arose by cross pollination to form a hybrid and then some astute farmer or gardener planted out the saved F2 seeds, made selections and kept doing that until the final selection was OP, which takes from maybe 3 to 10 years. And the explanation of how that works is in the link I gave above. The cross pollination is not between mutated plants if I understand what you're trying to tell me.

I've seen estimates that say about 95% of OP varieties arose in that manner and only about 5% arose by mutation from a preexisting variety.

But it's good to know that there are also about 12 different species of tomatoes of which only our garden tomato and two others are edible.

3. Can a plant be reverse bred to "dehybridize" it? Can you know without examining and comparing the genome of the plants?

A known F1 hybrid can sometimes be dehybridized to an OP version. It depends on how many parental genetic inputs there are, to a certain degree. There are OP versions of Sungold F1 and Ramapo F1 and Better Boy F1 and Santa F1 and some others and how close they come to the original F1 is subject to individual opinion.

If the new OP walks, talks and tastes close to the original F1 that's about all one can use for assessment b'c DNA sequencing cannot be done for direct comparison b'c not all the genes in the tomato genome are known although it's an area of extreme interest and the Tomato GEnome Project at Cornell is comprised of a lot of researchers who continue to ID tomato genes, as do others not based at Cornell who then report back their findings.

There have been instances where a commercial famer has maintained that seeds purchased were not what they should be and there are a few commercial labs that deal with those situations in terms of limited DNA sequencing to determine of the seeds sold were what they should be re any lawsuits that might arise.

But I do know of some work, not published, where certain OP varieties are being compared in terms of origin of certain genes, not the whole genome. There is some related work in terms of evolution of tomato shape and size available and was the subject of an article in an issue of Scientific American last year and the cover picture of that issue was showing some of the results.

4. Can a hybrid plant be bred through successive generations which will result in a hybrid which will always breed true in the future?

No, if you're talking about doing it via saved seed, thus sexually.

Yes, if you're talking about vegetative propagation by using lateral branches, aka suckers, which is cloning, to perpetuate the hybrid.

If I missed something or didn't explain it sufficiently please ask me again.

Carolyn