Color Genetics (GWR x Red)

jmsieglaff · November 15, 2015

I've been using some links, at least a couple of which come from members here:

http://frogsleapfarm.blogspot.com/20...-color-in.html
http://the-biologist-is-in.blogspot....-tomatoes.html
http://kdcomm.net/~tomato/gene/genes3.html

In preparation for growing F2 next year of a GWRxRed tomato I wanted to know what to expect ignoring other factors like skin color, dwarf/non-dwarf, etc. Below is my summary of the F2 for GWRxRed--please correct me where I am wrong.

Assuming the following F1 genetics: Rr and xgf (xgf is my representation of my understanding of the gf gene--either present or not so I used xgf notation).

F2:
9 red
3 yellow
3 black
1 gwr

3 red will fixed, 6 hetero. 3 red will have no gf, 6 will be hetero for gf.
3 yellow are all fixed. 2 will be hetero for gf, 1 no gf.
1 black is fixed (RRgfgf), 2 will be hetero for Red (Rr). All are fixed for gf.
1 gwr is fixed (rrgfgf)

I'm ignoring skin color. Now given these F1 are coming from an indeterminate/dwarf cross, getting these on a dwarf, so another variable and more rare than the above--but I did the colors regardless of indet/dwarf.

Did I make any mistakes?

ChrisK · November 15, 2015

Punnett square generator that can handle more than your dihybrid example. Make sure you indicate in the radio buttons which are dominant.

http://scienceprimer.com/punnett-square-calculator

Darren Abbey · November 15, 2015

Your calculations look about right. You'll have to grow 16 plants for reasonable odds of finding a Gwr plant.

Last year I grew out 12 F2s from a micro crossed to a normal plant and found one new micro. Micros have [at least] two separate dwarfing genes, so I would have needed to grow 16 plants to expect to find the desired result. I lucked out and found one. The plant itself was mostly a failure, but I saved seeds to see how it would do in better growing conditions. I learned how to screen the seedlings for the micro trait, so I hope to grow many, many more next year. I saved something like a thousand seeds from the F1 plant, so I would have plenty of F2s to explore over several years.

If you want to ensure you find a gwr F2, you'll have to grow out a larger number. You can grow the F2s over several years if you don't have the space to grow many at one time. Even if you find one while growing a small number of F2s, the plant may have other faults that lead you to choose to not continue it.

Indeterminate vs. determinate (sp, "self-pruning") is another gene. Normal vs. dwarf (d, "dwarf") is another gene. If you want to expect to find a determinate, dwarf, Gwr... you'll have to grow out at least 256 plants. Fortunately, you can identify dwarf plants when they are seedlings. This means you can start a very high number, but only grow out those that will have the dwarf growth habit. Supposedly you can identify determinate vs. indeterminate growth early on as well, so you can only grow out plants that have both features to adulthood. This will make it much easier to find your target plant than the raw probabilities suggest.

jmsieglaff · November 15, 2015

Thanks guys. Great link, I'm going to play around with the squares.

Fusion_power · November 16, 2015

A lot depends on the genetics of your original GWR. One possibility that may show up is a very bright cherry red that I've seen out of a Cherokee Green cross.

Have you put together a list of all the traits you want to select?

jmsieglaff · November 16, 2015

The two parents are Mexico Midget and dwarf Summertime Green. This F2 seed is part of the dwarf project, these are some crosses Craig did this year (http://www.tomatoville.com/showthread.php?t=38498). I don't have any specific traits I'm seeking out--I was more just thinking about what to expect. The only two trait I will specifically seek out are intensely flavored tomatoes and cherry size. If there are specific goals for the project I'll seek those out as well. I'm just excited to grow this cross (I will also be growing real Mexico Midget as well as Green Giant (a Summertime Green parent)).

2016 will be the first time growing out F2 seed and I'm excited for surprises it will bring. I'll be growing out these F2 tomato seeds as well as my squash project F2 seeds.

travis · November 16, 2015

My experience regarding what you ask is that you may expect some of the "blacks" to later segregate to green-when-ripe, and GWR/Bicolor. (I'm not sure if I understand you accounting for that with "1 black is fixed (RRgfgf), 2 will be hetero for Red (Rr). All are fixed for gf.")

And you might expect later segregations to bicolors in the yellows, green-when-ripes, and some of the "blacks," especially if using Summertime Green, a line (and a few of its sister lines) in which I got several bicolors when growing them during the F3 thru F5 generations, back when. (Not sure if those genetics were fully segregated out in the final prodjuct, which I have not grown since it was introduced.)

Side note: Glad to see someone outcrossing Summertime Green to Mexico Midget as Summertime Green and its sister lines can use a bit of heatset capability and common disease resistances. Hope you eventually get some nice compact indeterminate cocktail size tomatoes and a few nice cherry dwarves.

jmsieglaff · November 16, 2015

Quote:

Originally Posted by travis

My experience regarding what you ask is that you may expect some of the "blacks" to later segregate to green-when-ripe, and GWR/Bicolor. (I'm not sure if I understand you accounting for that with "1 black is fixed (RRgfgf), 2 will be hetero for Red (Rr). All are fixed for gf.")

Yes, that's what I mean. If I understand black tomatoes gf needs to be from both parents to be expressed--so any black tomato will have gfgf and that is then locked. However, 2/3 black tomatoes will be Rr, so seed saved from those may segregate to other colors in the F3. (Any black tomato that is RRgfgf will be black in all subsequent generations.)

Quote:

Originally Posted by travis

Side note: Glad to see someone outcrossing Summertime Green to Mexico Midget as Summertime Green and its sister lines can use a bit of heatset capability and common disease resistances. Hope you eventually get some nice compact indeterminate cocktail size tomatoes and a few nice cherry dwarves.

I'm excited to see where this cross takes everyone--I see Linda10 already started 20 F2 seeds out in California!

travis · November 17, 2015

Are those who are participating in this project supposed to be selecting solely for dwarf plants?

I ask, because some of us were involved in a project that crossed Red House Free Standing (dwarf) x Cherokee Green (indeterminate normal tomato leaf), and the segregations I liked the best recombined as regular leaf, compact indeterminates with substantially shortened intenodes, but non-dwarf. Those were real dandies.

Additionally, I crossed Tigerette (determinate, dwarf, elongated cherry) x Cherokee Purple, and also got (in addition to some awesome dwarf recombos), some very nice, substantially shortened internode, compact indeterminates with saladette size fruit.

jmsieglaff · November 18, 2015

I'm guessing people can select whatever they want to grow--but ultimately that would be Craig's call since he was the one who provided me the Teensy F2 seeds. I plan on selecting for dwarf, but your post makes me want to till our backyard and grow out them all. My wife and kids wouldn't be so happy if I did that though! Sounds like had some fun crosses that yielded some, tasty and manageable indetermine varieties. Do you grow them still?

travis · November 18, 2015

Right now, they are on hold while I devote space to three of my other projects to develop striped saladettes that dont crack or fall from the vine.

November 15, 2015	#1
jmsieglaff Tomatovillian™ Join Date: Jan 2014 Location: Southern WI Posts: 2,742	Color Genetics (GWR x Red) I've been using some links, at least a couple of which come from members here: http://frogsleapfarm.blogspot.com/20...-color-in.html http://the-biologist-is-in.blogspot....-tomatoes.html http://kdcomm.net/~tomato/gene/genes3.html In preparation for growing F2 next year of a GWRxRed tomato I wanted to know what to expect ignoring other factors like skin color, dwarf/non-dwarf, etc. Below is my summary of the F2 for GWRxRed--please correct me where I am wrong. Assuming the following F1 genetics: Rr and xgf (xgf is my representation of my understanding of the gf gene--either present or not so I used xgf notation). F2: 9 red 3 yellow 3 black 1 gwr 3 red will fixed, 6 hetero. 3 red will have no gf, 6 will be hetero for gf. 3 yellow are all fixed. 2 will be hetero for gf, 1 no gf. 1 black is fixed (RRgfgf), 2 will be hetero for Red (Rr). All are fixed for gf. 1 gwr is fixed (rrgfgf) I'm ignoring skin color. Now given these F1 are coming from an indeterminate/dwarf cross, getting these on a dwarf, so another variable and more rare than the above--but I did the colors regardless of indet/dwarf. Did I make any mistakes? Last edited by jmsieglaff; November 16, 2015 at 09:36 AM.

November 15, 2015	#2
ChrisK Tomatovillian™ Join Date: Mar 2011 Location: Raleigh, NC Posts: 1,448	Punnett square generator that can handle more than your dihybrid example. Make sure you indicate in the radio buttons which are dominant. http://scienceprimer.com/punnett-square-calculator __________________ Blog: chriskafer.wordpress.com Ignorance more frequently begets knowledge: it is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science. --Charles Darwin

November 15, 2015	#3
Darren Abbey Tomatovillian™ Join Date: Jun 2012 Location: Minnesota Posts: 586	Your calculations look about right. You'll have to grow 16 plants for reasonable odds of finding a Gwr plant. Last year I grew out 12 F2s from a micro crossed to a normal plant and found one new micro. Micros have [at least] two separate dwarfing genes, so I would have needed to grow 16 plants to expect to find the desired result. I lucked out and found one. The plant itself was mostly a failure, but I saved seeds to see how it would do in better growing conditions. I learned how to screen the seedlings for the micro trait, so I hope to grow many, many more next year. I saved something like a thousand seeds from the F1 plant, so I would have plenty of F2s to explore over several years. If you want to ensure you find a gwr F2, you'll have to grow out a larger number. You can grow the F2s over several years if you don't have the space to grow many at one time. Even if you find one while growing a small number of F2s, the plant may have other faults that lead you to choose to not continue it. Indeterminate vs. determinate (sp, "self-pruning") is another gene. Normal vs. dwarf (d, "dwarf") is another gene. If you want to expect to find a determinate, dwarf, Gwr... you'll have to grow out at least 256 plants. Fortunately, you can identify dwarf plants when they are seedlings. This means you can start a very high number, but only grow out those that will have the dwarf growth habit. Supposedly you can identify determinate vs. indeterminate growth early on as well, so you can only grow out plants that have both features to adulthood. This will make it much easier to find your target plant than the raw probabilities suggest. __________________ http://the-biologist-is-in.blogspot.com

November 16, 2015	#6
jmsieglaff Tomatovillian™ Join Date: Jan 2014 Location: Southern WI Posts: 2,742	The two parents are Mexico Midget and dwarf Summertime Green. This F2 seed is part of the dwarf project, these are some crosses Craig did this year (http://www.tomatoville.com/showthread.php?t=38498). I don't have any specific traits I'm seeking out--I was more just thinking about what to expect. The only two trait I will specifically seek out are intensely flavored tomatoes and cherry size. If there are specific goals for the project I'll seek those out as well. I'm just excited to grow this cross (I will also be growing real Mexico Midget as well as Green Giant (a Summertime Green parent)). 2016 will be the first time growing out F2 seed and I'm excited for surprises it will bring. I'll be growing out these F2 tomato seeds as well as my squash project F2 seeds. Last edited by jmsieglaff; November 16, 2015 at 08:42 PM. Reason: Corrected Summertime Green parentage

November 16, 2015	#7
travis Tomatovillian™ Join Date: Jan 2006 Location: Evansville, IN Posts: 2,984	My experience regarding what you ask is that you may expect some of the "blacks" to later segregate to green-when-ripe, and GWR/Bicolor. (I'm not sure if I understand you accounting for that with "1 black is fixed (RRgfgf), 2 will be hetero for Red (Rr). All are fixed for gf.") And you might expect later segregations to bicolors in the yellows, green-when-ripes, and some of the "blacks," especially if using Summertime Green, a line (and a few of its sister lines) in which I got several bicolors when growing them during the F3 thru F5 generations, back when. (Not sure if those genetics were fully segregated out in the final prodjuct, which I have not grown since it was introduced.) Side note: Glad to see someone outcrossing Summertime Green to Mexico Midget as Summertime Green and its sister lines can use a bit of heatset capability and common disease resistances. Hope you eventually get some nice compact indeterminate cocktail size tomatoes and a few nice cherry dwarves. Last edited by travis; November 16, 2015 at 12:05 PM.

November 16, 2015	#5
Fusion_power Tomatovillian™ Join Date: Feb 2006 Location: Alabama Posts: 2,250	A lot depends on the genetics of your original GWR. One possibility that may show up is a very bright cherry red that I've seen out of a Cherokee Green cross. Have you put together a list of all the traits you want to select?

November 17, 2015	#9
travis Tomatovillian™ Join Date: Jan 2006 Location: Evansville, IN Posts: 2,984	Are those who are participating in this project supposed to be selecting solely for dwarf plants? I ask, because some of us were involved in a project that crossed Red House Free Standing (dwarf) x Cherokee Green (indeterminate normal tomato leaf), and the segregations I liked the best recombined as regular leaf, compact indeterminates with substantially shortened intenodes, but non-dwarf. Those were real dandies. Additionally, I crossed Tigerette (determinate, dwarf, elongated cherry) x Cherokee Purple, and also got (in addition to some awesome dwarf recombos), some very nice, substantially shortened internode, compact indeterminates with saladette size fruit.

November 18, 2015	#10
jmsieglaff Tomatovillian™ Join Date: Jan 2014 Location: Southern WI Posts: 2,742	I'm guessing people can select whatever they want to grow--but ultimately that would be Craig's call since he was the one who provided me the Teensy F2 seeds. I plan on selecting for dwarf, but your post makes me want to till our backyard and grow out them all. My wife and kids wouldn't be so happy if I did that though! Sounds like had some fun crosses that yielded some, tasty and manageable indetermine varieties. Do you grow them still?