Color Genes again..

NarnianGarden · July 25, 2015

Another question on genes determinating the fruit color, bear with me - I am fascinated with the subject..!

If two varieties have the same fruit color - red-, why are they completely different looking at their 'green stage'? Variety A (Mohamed) has very prominent dark shoulders from the beginning, while variety B (Heartbreaker) looks very pale, almost glowing in the dark - (a bit like Jaune Flamme looks when they're unripe)
Both are cherry tomatoes, and should be red when mature..
I am just baffled at this world of genes and how many are involved with color changes. Is there any reason as to why all the difference?

travis · July 26, 2015

Without a photo for reference, I'll venture the possibility that one tomato carries the dark green shoulder genes, and the other carries the uniform ripening (uu), light green shoulder genes.

http://www.bing.com/images/search?q=...6lw&ajaxhist=0

NarnianGarden · July 26, 2015

That is so cool, thanks for the info!
.. it begs the question, what is the green shoulders gene actually needed for, if the fruits ripen to their intended color even in its absence?

joseph · July 26, 2015

Panels of taste testers generally rank tomatoes with the 'green shoulder' gene as better tasting than tomatoes with the 'uniform ripening' gene.

travis · July 26, 2015

Quote:

Originally Posted by joseph

Panels of taste testers generally rank tomatoes with the 'green shoulder' gene as better tasting than tomatoes with the 'uniform ripening' gene.

I have seen similar statements made in various places, and there may be some truth to the assertion.

However, I have been working with several uniform ripening lines developed from a cross using Mozark as one parent, and found all the recombinations to have superior, full tomato flavor.

Mozark is a uniform ripening open pollinated type with very good flavor, but when I crossed it to Sioux, the resulting lines were even better tasting, including the ones that have recombined as uniform ripening, light green shoulders.

The same is true of a few of the uniform ripening recombinations I've developed from Cherokee Purple x Summerpink.

So, I think it depends upon the tomato varieties themselves. Maybe it's a situation where the u/u types offered to the taste testing panels were just not all that flavorful in and of themselves, and for whatever other reasons as well.

Darren Abbey · July 26, 2015

This is a topic I've researched a bit...

http://the-biologist-is-in.blogspot....-tomatoes.html

Travis's comments hint at other genetics impacting the trait. A gene's impact always depends on the sum of all the other genes in an organism.

travis · July 27, 2015

Quote:

Originally Posted by Darren Abbey

This is a topic I've researched a bit...

http://the-biologist-is-in.blogspot....-tomatoes.html

Travis's comments hint at other genetics impacting the trait. A gene's impact always depends on the sum of all the other genes in an organism.

Thank you for the link to a short and informative article on uu and rin genetics.

We probably should keep in mind that many of the tomato varieties sold today as fresh market tomatoes carry both the uu and the rin genetics, and therefore suffer from twice the flavor suppression, so to speak, compared to heirloom and heritage types with the old, dark green shoulder traits.

So, possibly the flavor panelists were offered varieties carrying both uu and rin genetics. And generally, I would agree those types are rather flat tasting.

I think it has a lot to do with the types and quantities of chloroplasts present in dark green shouldered varieties vs light green shouldered, uu-type modern lines. And I think the linked article points to that issue.

Lately, some professional breeders have introduced another set of genes to the rin and uu fresh market type lines ... high crimson ogc ... for example Tasti-Lee, and think the resulting increase in chloroplasts has a positive effect on flavor ... however slight it may appear in Tasti-Lee.

It may be interesting to note that I have some recombinations of the Cherokee Purple x Summerpink cross that have shown high crimson expression. Whether this comes from Summerpink, a modern, uniform ripening pink determinate, or whether it comes from some genetics associated with the gf traits in Cherokee Purple, I do not know.

I do know that the gf genetics in Cherokee Purple attribute lots of chloroplasts to the mix, and thereby maybe the full flavor I get from some of the uu recombinations. I wish I knew more about the possible link between gf and ogc, if there is one.

NarnianGarden · July 27, 2015

Thank you! super interesting - I currently have two 'green shoulder' red cherry varieties (Mohamed & Sweet Million F1) and they have very prominent dark green on the fruits. I wonder if they'll taste better than the Heartbreaker - probably, I have read it is nithing special flavor-wise (sure looks pretty in the flowerpot!)

travis · July 27, 2015

"At some point before the 1930s, a farmer in the USA noticed a plant producing tomatoes that didn't have green shoulders (at left) and that ripened uniformly from top-to-bottom."
http://the-biologist-is-in.blogspot....-tomatoes.html (the article linked in Post #6)

I wish I knew WHEN EXACTLY "before the1930s," and which particular variety. Because I have seen "heirloom" tomatoes with the uu uniform ripening trait.

FLRedHeart · July 29, 2015

Quote:

Originally Posted by travis

"At some point before the 1930s, a farmer in the USA noticed a plant producing tomatoes that didn't have green shoulders (at left) and that ripened uniformly from top-to-bottom."
http://the-biologist-is-in.blogspot....-tomatoes.html (the article linked in Post #6)

I wish I knew WHEN EXACTLY "before the1930s," and which particular variety. Because I have seen "heirloom" tomatoes with the uu uniform ripening trait.

Bill, US farmer or no US farmer, it seems to me the year was about 1926 and the you might try researching the mutant of the variety Ailsa Craig which was named Devon Surprise, seems to be the beginning of the uniform gene in research... which was pursued by John MacArthur (Toronto), perhaps in his 1928 paper(?).
Cheers

maf · July 29, 2015

I don't think it has been mentioned in the thread yet that the tomato fruits themselves contribute to photosynthesis. So, all other things being equal, the increased chloroplasts in the dark green shoulders will produce more carbon compounds (sugars) in those fruits than is possible in the uniform ripening ones.

Obviously you can have good and bad tasting fruit of either type, depending on other characteristics, but given the choice I always go for the green shoulders as it seems to have more potential.

NarnianGarden · July 29, 2015

Quote:

Originally Posted by maf

I don't think it has been mentioned in the thread yet that the tomato fruits themselves contribute to photosynthesis. So, all other things being equal, the increased chloroplasts in the dark green shoulders will produce more carbon compounds (sugars) in those fruits than is possible in the uniform ripening ones.

Obviously you can have good and bad tasting fruit of either type, depending on other characteristics, but given the choice I always go for the green shoulders as it seems to have more potential.

That's very interesting. I would imagine that green shoulders attribute to the flavor and sugar content. The pale green Heartbreaker F1 with u/u is said to be not so special in the flavor department. It sure is eye candy with the strong green foliage, but somehow those pale green fruits look somewhat... lacking

bower · July 30, 2015

Well... this has been a year of gazing at green fruit for me, alright. So cold, so slow, and so many F2's I don't know what the colour or the taste will be like. I've been watching the green shoulders, the green 'stripey' thing on some... many undecided thoughts about the green fruit.

I'm seeing some dramatic differences in the segregating fruit, re how much green is present in the unripe, and whether it's all about the shoulders or instead develops as stripes or green patches throughout.....

Also wondering about the effect of conditions this season (cold and dark!), and noticing for example that Moravsky Div has the greenest shoulders ever this year (and they sure are tasty), but also, the Jagodkas have a green shoulder half way down the fruit, very dark, and they are the sourest fruit you ever tasted. Intense? Yes. Intensely sour.

My two farmer buddies are my 'taste panel' and get called in when there's something ripe to be evaluated.... I put Jagodka in the lineup one day, and it was hilarious...the other fruit were either tasty or bland, but when J came along, my friend actually recoiled from the sudden sourbomb.

So I feel pretty certain when I say, green shoulders don't mean sweet fruit.

NarnianGarden · July 31, 2015

OK, bower! Good to know. My first ripe fruit this year seems to be Golden Nugget.. very visible green shoulders before the golden hue takes over... I am waiting and waiting for that first bite, wanting to be ready I won't pick it too early. Sourbombs can have their place in cooking, but snacks need to have somewhat pleasant taste

July 25, 2015	#1
NarnianGarden Tomatovillian™ Join Date: Jun 2013 Location: Finland, EU Posts: 2,550	Color Genes again.. Another question on genes determinating the fruit color, bear with me - I am fascinated with the subject..! If two varieties have the same fruit color - red-, why are they completely different looking at their 'green stage'? Variety A (Mohamed) has very prominent dark shoulders from the beginning, while variety B (Heartbreaker) looks very pale, almost glowing in the dark - (a bit like Jaune Flamme looks when they're unripe) Both are cherry tomatoes, and should be red when mature.. I am just baffled at this world of genes and how many are involved with color changes. Is there any reason as to why all the difference?

July 26, 2015	#2
travis Tomatovillian™ Join Date: Jan 2006 Location: Evansville, IN Posts: 2,984	Without a photo for reference, I'll venture the possibility that one tomato carries the dark green shoulder genes, and the other carries the uniform ripening (uu), light green shoulder genes. http://www.bing.com/images/search?q=...6lw&ajaxhist=0

July 26, 2015	#4
joseph Tomatovillian™ Join Date: May 2013 Location: Cache Valley, N/E of The Great Salt Lake Posts: 1,244	Panels of taste testers generally rank tomatoes with the 'green shoulder' gene as better tasting than tomatoes with the 'uniform ripening' gene.

July 26, 2015	#6
Darren Abbey Tomatovillian™ Join Date: Jun 2012 Location: Minnesota Posts: 586	This is a topic I've researched a bit... http://the-biologist-is-in.blogspot....-tomatoes.html Travis's comments hint at other genetics impacting the trait. A gene's impact always depends on the sum of all the other genes in an organism. __________________ http://the-biologist-is-in.blogspot.com

July 27, 2015	#8
NarnianGarden Tomatovillian™ Join Date: Jun 2013 Location: Finland, EU Posts: 2,550	Thank you! super interesting - I currently have two 'green shoulder' red cherry varieties (Mohamed & Sweet Million F1) and they have very prominent dark green on the fruits. I wonder if they'll taste better than the Heartbreaker - probably, I have read it is nithing special flavor-wise (sure looks pretty in the flowerpot!)

July 29, 2015	#11
maf Tomatovillian™ Join Date: Jun 2010 Location: England Posts: 512	I don't think it has been mentioned in the thread yet that the tomato fruits themselves contribute to photosynthesis. So, all other things being equal, the increased chloroplasts in the dark green shoulders will produce more carbon compounds (sugars) in those fruits than is possible in the uniform ripening ones. Obviously you can have good and bad tasting fruit of either type, depending on other characteristics, but given the choice I always go for the green shoulders as it seems to have more potential.

July 30, 2015	#13
bower Tomatovillian™ Join Date: Feb 2012 Location: Newfoundland, Canada Posts: 6,794	Well... this has been a year of gazing at green fruit for me, alright. So cold, so slow, and so many F2's I don't know what the colour or the taste will be like. I've been watching the green shoulders, the green 'stripey' thing on some... many undecided thoughts about the green fruit. I'm seeing some dramatic differences in the segregating fruit, re how much green is present in the unripe, and whether it's all about the shoulders or instead develops as stripes or green patches throughout..... Also wondering about the effect of conditions this season (cold and dark!), and noticing for example that Moravsky Div has the greenest shoulders ever this year (and they sure are tasty), but also, the Jagodkas have a green shoulder half way down the fruit, very dark, and they are the sourest fruit you ever tasted. Intense? Yes. Intensely sour. My two farmer buddies are my 'taste panel' and get called in when there's something ripe to be evaluated.... I put Jagodka in the lineup one day, and it was hilarious...the other fruit were either tasty or bland, but when J came along, my friend actually recoiled from the sudden sourbomb. So I feel pretty certain when I say, green shoulders don't mean sweet fruit.

July 31, 2015	#14
NarnianGarden Tomatovillian™ Join Date: Jun 2013 Location: Finland, EU Posts: 2,550	OK, bower! Good to know. My first ripe fruit this year seems to be Golden Nugget.. very visible green shoulders before the golden hue takes over... I am waiting and waiting for that first bite, wanting to be ready I won't pick it too early. Sourbombs can have their place in cooking, but snacks need to have somewhat pleasant taste