Sounds right to me and in my experience with saving the seeds fruit size - as long at it is fully mature before you harvest the seed - doesn't affect the next generation. You can save them with confidence. Smaller fruit later in season seems to be more the result of plant age and weather than genetics.

Good luck.

Dave

Dave's information is correct. The genetic makeup of fruit from a single plant is identical regardless of the size of the tomato. Saving fruit from a plant that consistently gave larger fruit would be a different matter.
Jim

So..........How would you know if the seed you had extracted would continue to produce the fruit you wanted to see and or taste?

In other words extracting seed from a fruit that was large, on a plant that had an abundance of large fruit would produce the same if you extracted from a fruit from the same plant, that was small?

So if you are growing out a certain type you can rely on any fruit from the plant for the next generation ...or F

In other words extracting seed from a fruit that was large, on a plant that had an abundance of large fruit would produce the same if you extracted from a fruit from the same plant, that was small?

Yes. A large fruit seed plant may very well produce some small fruit too. Weather and age of the plant as well as available nutrients can affect fruit size. But the genetics of the plants seed are all the same (assuming no accidental crossing). A seed is a seed is a seed. ;)

Dave

I emphatically disagree with the statement that all the seeds from the same tomato are genetically identical. Maybe they ought to be according to genetics (as a mechanical engineer/motorhead type this is foreign territory to me). However, God bless my teachers,I was trained in observation, analysis, and the importance of precise record keeping. When I was growing commercially I did a much better job of this than I do now, simply because then it was essentially important to my success.

Now I'm 73 and have probably made more observations and mistakes than I ever imagined possible Experience is a wonderful thing, don't you know, as it teaches us to recognize the same error time after time after-----.

I have done numerous multi plant variety tests, all with seed saved from the same tomato. And each seed tomato was carefully selected as a fine example from which to carry on the line! Some tests I did with plants dispersed through my several gardens, these planted immediately adjacent to a another variety I wanted to compare. Dispersal offered variable exposure to soil conditions, weather exposure, desease organisms, etc. Or, I planted in rows, perhaps 6 of the one variety adjacent to six of another variety, these in rows side by side.

SEEDS FROM THE SAME TOMATO DO NOT PERFORM IN SUCH A WAY AS TO CONCLUDE THERE IS GENETIC IDENTITY.

This probably will underscore my technical ignorance but I
have often rationalized this by noting the difference between puppies in the same litter, or even identical human twins. And we also know about non-identical twins, like the Bush girls. And different as they are I'm pretty sure George and Laura love them both very much.

Now before one of ya'll genetically savvy types out there
commences to destroy my position and arguments, please take pitty on a frail old man and do please leave me with a tad of self respect!

I emphatically disagree with the statement that all the seeds from the same tomato are genetically identical.
**************

I presume your statement considers a stable variety without cross polination.......

If seeds from the same tomato are NOT genetically identical,

How genetically DIFFERENT can they be?

Will the differences be noticable by a 'casual' observer.

Please give examples.

John

Maybe I can shed a bit of light here b'c I have talked about biological divsersity within a single variety before, actually several times and also quite recently here at GW.

I presume your statement considers a stable variety without cross polination.......

****

No, he's talking about genetic diversity with complete pollenization and without cross pollination.

*****
If seeds from the same tomato are NOT genetically identical,

How genetically DIFFERENT can they be?

Will the differences be noticable by a 'casual' observer.

Please give examples.

*****

Spontaneous mutations occur all the time but are usually so subtle that the causal observer may or may not see differences unless they're looking for them.

And in any case the variety is still recognized as the same variety b'c the subtle changes don't change the basic traits of the variety that are used to recognize it.

Take 20 seeds of a single variety and set out the plants.

What you may see are some plants that have different internode differences, have subtle differences in leaf shape, but not going from RL to PL or vice versa, some plants may ripen fruits before others, etc.

A person trained in tomato genetics, which I'm not, can see other differences as well but I've forgotten what those are right now. Keith, ( OLTV, or similar) who posts here often and is trained in tomato genetics having gotten his MA degree with Dr. Randy Gardner, a world wide known tomato hybridizer at NCSU who developed the Mountain series and many more and who just retired, has spoken to this issue several times before as well.

So we're not talking about cross pollination, we're talking about biological diversity within a single variety.

And b'c of the diversity it's suggested to never save seeds from just one fruit, to save seeds from many fruits on one plant and best is to save seeds from several fruits from several plants.

And that's if one is really trying to maintain the biological diversity within a variety, but few folks do that .

Carolyn

SEEDS FROM THE SAME TOMATO DO NOT PERFORM IN SUCH A WAY AS TO CONCLUDE THERE IS GENETIC IDENTITY.

****

Larry, from my explanation above of genetic divsersity with a single variety I'm afraid I can't agree with your above comment in toto.

I do agree to the extent that some seeds may have had subtle minor spontaneous mutations, but if you're implying that the variety is so changed genetically that it's a different variety, then I can't agree. ( smile)

The only way that one can definitively determine if the genes (DNA) have undergone mutation is to do sequence analysis of that DNA and yes it has been done, but rarely, when a large commercial farmer claims that the seeds purchased were not what they should be and then has sued the seed producer.

(Now before one of ya'll genetically savvy types out there
commences to destroy my position and arguments, please take pitty on a frail old man and do please leave me with a tad of self respect!)

So you're a frail old man of 73 and I'm an old lady of 69, so folks can take pity on both of us if they so wish. LOL

Carolyn

OK, what kind of differences havc I seen between plants grown from seed saved from the same fruit:

1.) First, I agree that the condition of stabilization certainly has a lot to do with it. Rutgers is pretty much going to be Rutgers. However, friend Charlie (who lives over there by Whatsienutsie) might offer you a magic giant oxheart that you just have to grow. "You're gonna love it!" This actually happened to me this year; I grew 6 plants for the dude in exchange for some seed. They were neither oxhearts, prolific, or magic in any way I could see. I kept two plants--one grew 2" reds while the other grew a medium sized globe shaped red with thick skins and a lot of size variability.

2) Yes, quite often heirlooms will throw different leaf types. Not at all uncommon.

3) Plant a row of 6 or more in soil you feel is pretty darn consistant, in a location not likely to be influenced irregularly in the row positions by light, wind, traffic,
etc, variables. You are likely to see what I feel are more than subtle differences in individual plant yield, fruit
quality and size consistancy, desease, plant height and limb developement. It has never been hard for me to decide which plant to save seed from! Having said that, there is absolutely no way for me to be absolutely sure I selected the best plant for seed source or the best fruit(s). And, over the years, I have had varieties cross or somehow mutate or whatever and go bad on me. Right now I am working on a project to save a lot of seed for a variety that about went extinct--Mozark. Carolyn, I selected seed from 5 fruits on one nice plant, have also got seed being generated in the Toledo area, and some cross town in Spike's garden, (over there by Whatsienutsie)! We are definately trying for diversity here!

3) This year, my daughter and I had a unique experience. She had traded for and grew in her garden a single plant of a variety called Northern Lights. It made strikingly beautiful large bicolored fruits, with an apple like gradation of colors on each fruit rather than a stripey difference in colors. We each took a nice sized fruit for seeds. Hers, she claimed, was delicious and there were not too many seeds inside. Mine was gelatenous on the interior, a bezillion seeds and little if any meat! Now there is an example of some diversity from the same seed, & same plant!

Larry

Right now I am working on a project to save a lot of seed for a variety that about went extinct--Mozark.

****

larry it might interest you to know that a person who posts here at GW got old seeds from U of MO and was able to germinate them and listed the variety in the SSE 2008 Yearbook, seeds available to SSE members only.

Bill gives the parentage for Mozark as well as how it was part of the parentage to many other varieties and names them as well.

Carolyn