Forum area for discussing hybridizing tomatoes in technical terms and information pertinent to trait/variety specific long-term (1+ years) growout projects.
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April 6, 2018 | #1 |
Tomatovillian™
Join Date: Feb 2011
Location: Northeast Wisconsin, Zone 5a
Posts: 1,109
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Determining color in rin lines
My brain has been working on this with no results for a while.
I've been playing with rin lines for several years, working on getting stripes and the Aft genes I want in rin lines so that I can someday make F1 ESL hybrids with the appearance genetics that interest me. Last year I finally got a F2 that had all three in it at a saladette size, this year I have 18 more F2 rin lines going out and 10 more F1 crosses with a rin/rin parent. What I'm curious about is that I've intentionally made crosses with the full color palette of tomatoes at my disposal, as I want to someday be able to make F1's in various colors as well. The challenge I have is how can I tell which color genes are present in a non-ripening line other than by crossing it to stable recessive color lines to see what the resulting F1's are? As it is I can only come up with making selections for phenotype at F2 and then the following season making multiple crosses then growing those out to attempt a determination as to the color genes in the rin lines. Is there any other option? |
April 6, 2018 | #2 |
Tomatovillian™
Join Date: Dec 2016
Location: Pittsburgh, PA
Posts: 3,194
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Can you wait until the tomatoes eventually ripen, and see what you get?
Nan |
April 6, 2018 | #3 |
Tomatovillian™
Join Date: Feb 2011
Location: Northeast Wisconsin, Zone 5a
Posts: 1,109
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rin is non-ripening, so a rin/rin breeding line for making F1 ESL hybrids with will never show the fruit color. The most you end up with is some yellowing as they mature.
In rin lines that have the crimson gene you will see a bit of red even in a rin/rin. But I'm interested in the colors you don't normally see in these lines. So if a rin/rin line has the tangerine gene or the gf gene for example, you can't tell from the fruit or the plant. I'm trying to figure out if there is an easier way than making 4-5 crosses with each F3 plant and trying to determine which color genes they have to make further selections. |
April 6, 2018 | #4 |
Tomatovillian™
Join Date: Dec 2016
Location: Pittsburgh, PA
Posts: 3,194
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How do you even know you have the color stabilized in your rin/rin lines? I guess a dna analysis could tell you, but in practicality, you might have to make the crosses.
Nan |
April 6, 2018 | #5 |
Tomatovillian™
Join Date: Feb 2011
Location: Northeast Wisconsin, Zone 5a
Posts: 1,109
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DNA testing is a possibility, but I don't know if there are labs doing MAS testing that even offer the color options.
My hope is there is some combination of "cross with these 4 or 5 stabilized flesh colors and with this chart you can figure out what color genes are present based on the F1 traits." that gives me a good idea of what is in the unstable rin line. Sent from my SM-G930V using Tapatalk |
April 8, 2018 | #6 |
Tomatovillian™
Join Date: Jun 2012
Location: Minnesota
Posts: 586
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The rin mutation inhibits ethylene production, thus interfering with ripening. You should be able to test your fruit by ripening them the same way grocers do, with supplemental ethylene. A simple source is ripening bananas in a bag or other sealed container. It'll probably take some experimenting to figure out the best ripening induction protocol for you.
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April 8, 2018 | #7 | |
Tomatovillian™
Join Date: Feb 2011
Location: Northeast Wisconsin, Zone 5a
Posts: 1,109
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Quote:
Sent from my SM-T550 using Tapatalk |
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April 8, 2018 | #8 |
Moderator Emeritus
Join Date: Jan 2006
Location: Upstate NY, zone 4b/5a
Posts: 21,169
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Try the link below and look for Dourne de Hivre,a variety sent to me by Norbert in France in 1992.
Mark McCaslin,aka Frog Leaps's Farm,was looking for rin mutants so I sent him this one. Fruits so had I almost had to get a hachett to get the seeds out, but I will say the fruits were beautiful with colors of orange,e, red,pink and yellow. I had SSE listed it hoping that someone would use it in a cross to preserve the colors but no one did. https://www.google.com/search?q=Dour...&bih=815&dpr=1 Carolyn,just noting that rin is one, and the alc gene is another one as well.
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Carolyn |
April 8, 2018 | #9 |
Tomatovillian™
Join Date: Feb 2011
Location: Northeast Wisconsin, Zone 5a
Posts: 1,109
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I remember the discussions about Dourne de Hivre, I wish it was available somewhere.
I've got about 10 alc lines queued up for next year, but the dry cultivation where they tend to do best isn't usually an option for me here. I'm hoping to finally put up a greenhouse this year so I can control the water input. Fortunately alc doesn't have the color guessing game factor. Sent from my SM-T550 using Tapatalk |
April 9, 2018 | #10 |
Tomatovillian™
Join Date: Jun 2012
Location: Minnesota
Posts: 586
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I'd love to hear about any experiments you do. I haven't grown any rin/rin lines to be able to test the idea out.
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April 16, 2018 | #11 |
Tomatovillian™
Join Date: Nov 2008
Location: Minnesota
Posts: 568
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Mark, there are molecular markers commercially available for a few of the color genes, but not all. I think there is no alternative to making test crosses once the rin lines are stable. The rin mutant controls ethylene production, and also directly controls down-stream ethylene meditated ripening processes. An ethylene treatment is unlikely to ripen these fruit.
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