Member discussion regarding the methods, varieties and merits of growing tomatoes.
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September 16, 2010 | #1 |
Tomatovillian™
Join Date: Jan 2010
Location: NW Indiana
Posts: 1,150
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PPP x PP "C"
Does anyone know what, if anything, became of this cross? I noticed it on Tania's site, but the notes there seem to all be several years old. Curious if it died on the vine (pardon the pun) or evolved into a distributed variety.
Rich |
September 16, 2010 | #2 |
Tomatovillian™
Join Date: Jan 2006
Location: Texas
Posts: 3,027
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I've been listing it in the yearbook (with Denise's permission) for the last couple of years. In the 2010 yearbook, there were two listers for this variety - IL LO N and myself. I'm up to either F6 or F7 with it at this point.
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September 16, 2010 | #3 |
Tomatovillian™
Join Date: Feb 2008
Location: Mid-Ohio
Posts: 848
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I got it in a trade last year and grew it (F5 I think). Its a very good and very pretty tomato. Mine were a bit smaller and better shaped than the pics at Tatianas.
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September 16, 2010 | #4 |
Tomatovillian™
Join Date: Jan 2010
Location: NW Indiana
Posts: 1,150
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Thanks for the feedback. It looks like a very nice tomato. Is it relatively stable at this point?
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September 17, 2010 | #5 |
Tomatovillian™
Join Date: Jan 2006
Location: Anmore, BC, Canada
Posts: 3,970
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It is very much alive - unfortunately I am out of seed at the moment, and will need to regrow it in the future.
It is a very good tomato indeed. Tania
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Tatiana's TOMATObase |
September 17, 2010 | #6 |
Tomatovillian™
Join Date: Feb 2008
Location: Mid-Ohio
Posts: 848
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Is it stable? I would have to say No and it never will be. It was traded out well before the completely stable F7 generation so each person that has it can have a unique gene pool, and since home gardeners are not generally selecting for specific traits when they save seeds, what little bit of variation was in the original release is probably still out there.
But then again it depends on your definition of stability. Will it be a mid size to large black, potatoleaf and taste good? Yes. Will they all have exactly the same production, size, and shape the way they would if selected all the way to F7? I doubt it. |
September 17, 2010 | #7 |
Tomatovillian™
Join Date: Feb 2006
Location: MA
Posts: 4,971
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I may still have some F3 seed of PPP x PP "A", "B", and "C". I'll look for it over the weekend.
Gary Last edited by Tormato; September 18, 2010 at 11:27 AM. |
September 17, 2010 | #8 |
Tomatovillian™
Join Date: Jan 2006
Location: Evansville, IN
Posts: 2,984
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I think we need to differenciate in this case between stability of a line coming out of this cross and standardization of PPPxPP"C" as a variety.
I'd say that if you got F7 seeds from Suze for PPPxPP"C" that line is probably stable or pretty close to it. However, if you got F7 seeds for PPPxPP"C" from another person who also has been growing his or her line out for several generations, the likelihood is that this second PPPxPP"C" F7 will vary a bit from (not be standard with) Suze's F7 line. But both F7 lines may themselves be stable separately from each other and separately from the issue of a standardized variety. |
September 17, 2010 | #9 |
Tomatovillian™
Join Date: Feb 2008
Location: Mid-Ohio
Posts: 848
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There may or may not be increased stability due to genetic drift (planting of relatively few seeds picked at random), but I would argue that there has been very little active selection, which would stabilize the line much faster. F7 is the fastest that the desired level of stabilization can be reached under intense selection.
To actively/systematically stabilize a line you would have to grow several plants and select one plant to preserve the traits of the parent plant through comparison. I doubt that many seed savers do that. They grow a couple of plants minimum and as long as the plants seem to be what they are supposed to be, seeds are saved from all of them, thus preserving the genetic variability. If I threw out all of the extra seeds I got in trade and just saved seeds from one of the plants I did grow, my line would be more stable, but I saved seed from both plants and will go back and plant any of the original seeds next year to use them up, so I can't really say that my F6 seed is any better (more stable) than the F5 seed I obtained. If Suze saved seed from only one plant each in generations F3, F4, F5, F6, F7, then her's is pretty well stable at F7. If she she saved seed from three very similar plants in F4, and kept growing plants from that mixed seed for the next three generations, then her F7 seed could at the minimum be only as stable as the combined three F4 plants. It probably doesn't matter too much for this cross because it is inbred to start with [OP x PP]xPP so what little variation that shows up past the selection of the "C" line might be hard to notice (i.e. it was "practically" stable when it was sent out even if not theoreticaly stable). |
September 17, 2010 | #10 | |
Tomatovillian™
Join Date: Jan 2006
Location: West Coast, Canada
Posts: 961
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Here are brief notes from my original grow out
Quote:
And a pic - well worth checking out all three - I may have a few seeds left from 2006 if anyone is really interested in growing these out ...
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D. |
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September 17, 2010 | #11 |
Tomatovillian™
Join Date: Jan 2007
Location: PNW
Posts: 4,743
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I think you can save seeds from multiple different F2, F3,
or F4 plants together, as long as at some point you reduce the selection to only saving from one plant. If I grow, say, 8 F3s, and I save seeds from 3 of them with excellent, if slightly different, flavors, and different productivities, then my F4 plants from those seeds are going to be quite mixed. But any one of those F4s could be what I am looking for, regardless of which F3 parent it came from, and it might be the only one at that generation that I save seeds from. Or there might be another 3 excellent F4 plants, each of which could have grown from F3 seeds of any of the 3 parent lines that I saved seeds from. So I save seeds from all 3 of the good F4s, together. Then my F5 plants are going to be from a few different lines of selection, too. At that F5 generation, though, I am probably going to pick one best plant to save seeds from, and its parentage is going to be whatever it would have been if I had only saved seeds from the 1 F2 that produced the 1 F3 that produced the 1 F4 that produced that F5 plant (if cross-pollination by bees at any of those steps did not happen). I am simply testing less parallel possible selections from the same parent plant at each generation in my fixed number of 8 plants than I would have been if I only had saved seeds from one plant at each of F2, F3, and F4 generations. In a given F4 year, out of 8 plants I might have 2 plants from seeds of 1 F3, 2 plants from seeds of a 2nd F3, and 4 plants from seeds of a third F3 plant, instead of 8 plants from any one of those. If in some year I only save seeds from one plant, then the progress toward stability of that line is the same as if I had only been growing that one line all along. I have simply tested less of the possibilities of seeds from each of its parent, grandparent, and great-grand-parent plants than I would have if I had only saved seeds from 1 F2, 1 F3, and 1 F4 plant. How well that works, whether you have to go back to your F2, F3, or F4 seeds and test other genetic combinations in those seeds to get something that you consider worth stabilizing, is basically luck, unless you can grow rows of a thousand F? plants or similar. I had 15 F4s of a basket cherry project this year and 3 last year from a mix of seeds from 2 F3 plants that had nearly identical flavors, and none of the F4s measured up to the taste of the best F3s. I did save F5 seeds from the best one, and I will grow out some F5 plants just to see what happens, but I expect to still need to go back to the F3 seeds to find an F4 plant with flavor that has the quality of the F3 plants that I saved those seeds from originally before I get the flavor that I want to stabilize in an OP. I only grew 7 F3s to find those two with great flavor, but I have now grown 18 of the F4s and 3 F5s from last year's best F4 without tasting it again. When you have mutliple people doing this from the same batch of F2 seeds, though, TZ-OH6 is right that what each selects is going to be a little different in each generation, so whatever they eventually stabilize should have different names than what the name of the F2 was, and a different name for each person's stable OP (with seeds saved from only one plant at F5, F6, and/or F7).
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-- alias Last edited by dice; September 19, 2010 at 03:53 AM. Reason: long line; sp |
September 18, 2010 | #12 |
Tomatovillian™
Join Date: Jan 2006
Location: Evansville, IN
Posts: 2,984
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I guess I'm defining stability differently, TZ.
To me the germplasm is 50% along it's way to stability at F2 because it's 50% heterozygotous and 50% homozygotous. At F3 the germplasm is 25% heterozygotous and 75% homozygotous. At F6 the germplasm is 3.125% heterozygotous, and at F7 it's only 1.56% heterozygotous and over 98% homozygotous are darn near fully stable. Yes, if each person growing out PPPxPP"C" who got their seeds back when it was F2 or F3 annually made single plant selections from which to save seed, then each grower has his own stable line at F7. But my point is that I would consider each single plant selection line to be stable but not standard except by the most remote coincidence. However, I do have a problem with your premise that one should select each generation to a standard set by the original F1. That would negate a whole lot of very unique and wonderful varieties we now enjoy that were selected from quite diverse expressions that recombined in the F2 or F3 siblings from crosses made similarly to how PPPxPP began. For example, Dora, Bear Creek, Gary'O Sena and Liz Bert, all of which are diverse sibling lines from an original cross of Brandywine and Cherokee Purple and not all of which mirror the F1. |
September 18, 2010 | #13 |
Tomatoville® Moderator
Join Date: Jan 2006
Location: Hendersonville, NC zone 7
Posts: 10,385
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It all depends upon the goal - replicating as exactly as possible what was discovered in the F2, or trying to stabilize as many interesting things as you can. With the Brandywine X Tad cross that yielded Little Lucky and Lucky Cross, it is only the tip of the iceberg - last year I named two others that I would like to stabilize - Large Lucky Red and Caitlin's Lucky Stripe...then there is Little Lucky Heart, and Striped Sweetheart.
In the Dwarf project, with Sneezy, we will end up having about 8-10 newly stable OPs from that one cross of Golden Dwarf champion and Green Giant - all very distinctly different.
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Craig |
September 18, 2010 | #14 |
Tomatovillian™
Join Date: Feb 2006
Location: MA
Posts: 4,971
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I found my stash of "A", "B", and "C" faster than I thought it would take. Searching through hundreds and hundreds of varieties is easy when one looks for Denise's blue envelopes. I have about a dozen seeds of each. PM me for them.
Gary |
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