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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March 20, 2014 | #1 |
Tomatovillian™
Join Date: Aug 2012
Location: Desert CA
Posts: 400
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A question about color traits
I was wondering about this and please forgive the analogy
In the orchid world an "alba" type flower is the result of recessive genes and lacks any coloration expect maybe some yellow towards the throat. If the albino is used as a seed plant then it normally will pick up color from the pollen parent and either A)will have some alba along with the donated color genes resulting in a bi color/tri color flower form or B) be one solid color because a color gene regardless of hue is a dominant trait in orchids Now as far as tomatos go Are GRW toms the same in that green is a form of albinism or lacking of true pigment? And if used as the "seed" parent plant do the F1's or F'2 then pick up similar color forms as the pollen parent? Or are the genetics hijacked by the pollen parents dominant traits and future segregation generally turns up the more dominant traits of the two? Sorry about asking such a base question, and using a strange analogy Gaston |
March 20, 2014 | #2 |
Tomatovillian™
Join Date: Oct 2011
Location: Durhamville,NY
Posts: 2,706
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My understanding of GWR tomatoes is that it is a mutation(s) that goof up the chemical pathway that converts chlorophyll to lycopene. In general it doesn't seem to matter which parent is which. From what I read here crossing a GWR tomato with another tomato that isn't GWR will give interesting results because the color genes are still there.
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March 20, 2014 | #3 |
Tomatovillian™
Join Date: Aug 2012
Location: Desert CA
Posts: 400
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Doug
Thanks for clarifying that for me. Now I see that it's actually unlike the genetics for floral albinism. In which case I'll have to try some crosses any hoo just for the experience of observing the outcome. Gaston |
March 21, 2014 | #4 |
Tomatovillian™
Join Date: Feb 2012
Location: Newfoundland, Canada
Posts: 6,793
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Just a quick answer from memory, of the little bit I know about.
There are several genes involved in tomato colour, as separate genes affect the colour of the skin and of the flesh. A red tomato, for example, has red flesh and a yellow epidermis: these traits are dominant to yellow flesh and clear epidermis. This gets more complicated with extra genes involved in reds such as 'high crimson', and genes like 'tangerine' and others that give an orange colour. Red flesh and clear epidermis gives pink. Black and GWR tomatoes have the 'gf' gene "green flesh" which causes them to retain chlorophyll in the flesh when they ripen. This is a separate trait from flesh colour, so that black tomatoes have flesh that combines both red and green. The browner looking fruits have yellow epidermis while the pinker looking ones are clear. |
March 21, 2014 | #5 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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There are 3 (4? or 5?) genes that give a form of orange. So how you'd differentiate which gene is being expressed in crossing of those without chemical analysis or gentic testing I don't know. (And it matters to me, as one kind of orange results in higher Beta carotene, another gives a higher Delta Carotene and still others give reduced pigment (i.e. less carotene/lycopene)
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April 7, 2014 | #6 |
Tomatovillian™
Join Date: Aug 2012
Location: Desert CA
Posts: 400
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Bower
Thanks for that answer concerning Chile traits and it helps a whole lot because one wouldn't normally consider the interactions between the epidermis and the flesh are what contribute to the perceived color of the fruits. This is really cool because it really broadens the curve on what to expect when it comes to what to expect from various crosses. |
April 7, 2014 | #7 |
Tomatovillian™
Join Date: Jun 2012
Location: Minnesota
Posts: 586
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I recently wrote a blog post about the basis for color in tomatoes. You might find it informative.
http://the-biologist-is-in.blogspot....-tomatoes.html In general, there are traits which depend on which parent the allele comes from… but in tomatoes, none have been noted in particular. |
April 7, 2014 | #8 |
Tomatovillian™
Join Date: Feb 2006
Location: Alabama
Posts: 2,250
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Nice DA. The split from lycopene to beta carotene appears to be a true Y split in the bio path. One side goes to lycopene and the other be carotene. It is possible to breed a tomato that has high levels of both lycopene and carotene though they appear as red tomatoes. Caro Red is an example of one mid-path expression.
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April 7, 2014 | #9 | |
Tomatovillian™
Join Date: Jun 2012
Location: Minnesota
Posts: 586
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Quote:
Do you have some references that might help me improve my understanding? Last edited by Darren Abbey; April 7, 2014 at 03:04 AM. |
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April 7, 2014 | #10 | |
Tomatovillian™
Join Date: Feb 2012
Location: Newfoundland, Canada
Posts: 6,793
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Quote:
http://jxb.oxfordjournals.org/content/58/14/3841.full Yeah, it is so interesting that different pigments are involved in peppers vs tomatoes. Flower pigments and the colours of eg beans are mostly anthocyanins, a whole other ball game, and mushroom pigments include some unique stuff as well...that is in the dye group rather than the food group! |
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April 7, 2014 | #11 | |
Tomatovillian™
Join Date: Dec 2010
Location: Sunol, CA
Posts: 2,723
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Wonderful blog post! Thanks.
Quote:
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April 7, 2014 | #12 |
Tomatovillian™
Join Date: Aug 2012
Location: Desert CA
Posts: 400
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Cr
I apologize for what is about to be a very base question. Are you breedspoke of about theing for nutritional improvements as as color? Or is it as fusion spoke of below and the higher beta carotene content would lead to more saturated pigmentation?. Bower I actually ment color traits., but I was replying from my phone and the auto correct hijacked the word at least it's as as some of the auto corrects that i have seen in the past. Although It is true on the fact that peppers also have some crazy neat traits going on when it comes to color and especially shape. The mushroom topic is on a whole other level and is in it self a topic worth finding out about. If nothing more than to apply some new technical knowledge to them. Btw thanks for that article. |
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