Another Tomato Genetics Question!

[FLRedHeart]

To sort of summarize my thoughts again, fruit sizes and the shapes related to them are generally, but not always, quantitative traits. This makes them difficult to casually breed a "prettier" tomato without growing out large quantities of plants, because 5, 10, or maybe 20 genes are involved for this type of trait.

All the different genes that play this game are varyingly expressed depending on environment and growing conditions which are constantly changing ... and not uniform throughout the plant and time, as flowers are blooming, making breeding of them for increased size or "beauty" a perplexing task.

That does not say that selection for increased size won't takle you in the right direction but it comes down to daunting statistics and optimistic expectations. Some gene mutations are easy to spot and more amenable to breeding efforts, if you got perhaps single gene mutation that you can recognize, such as a polka-dotted fruit color pattern, or simply a change to yellow from red.

In the laboratory the fruit color variation is likely more a qualitative trait, not a quantitative one. With fruit size it generally is not clear what is causing it. The process of increasing fruit size we have today is more related to the process of domestication since people like big fruits and over a hundred or a thousand years have managed to use selection pressure to get there. Some genes play a larger role than others of course, and sometimes there are game changing mutations such as going from two seed cavities (locules) to many.

A fruit formed in the home garden exculsively by mixed pollen from other varieties is a good way to think about breeding without the assistance from markers in the laboratory. The fruit itself likely won't look any different but just look at all that genetic variation its seeds contain for the breeder or enthusiast, like a cleverly hidden box of chocolates with a wonderland of different shapes and sizes inside!

When ted asked originally about selectively breeding beauty pagent winners, I compared this to size, because beauty may be different in his eyes than mine. It is best when trying to breed something, that it be defined to make the scope of the work manageable ... in other words directed to a specific goal, or things will get even more ambiguous and progress harder to measure. But it definitely keeps life interesting and I'm sure has resulted in many nice heirlooms, evn if they were by accident!

[Fusion_power]

Ted, if you really like Orange Minsk and you also like KBX, cross them. The segregating offspring will give tons of opportunity to select for better fruit shape and improved flavor.

I also agree with Joseph re epigenetics. Larger and healthier fruits produce seed that have slightly better performance when grown. This won't help much with catfacing which is associated with cold temperatures during pollination. Said another way, you will have to make some changes to the genetics to make progress against catfacing. As above, cross OM and KBX.

For general breeding, always select fruit from the best performing plant stipulating that the plant in question must not be a hybrid. I've had bee made hybrids in my garden where a single crossed plant outperformed the un-crossed seedlings dramatically. The crossed plant won't breed true and you will spend several years growing out seedlings trying to stabilize the genes of the hybrid. I have also grown out seed from single high performing plants and compared results with un-selected plants. The results are consistent that like breeds like - high performers produce high performers.

I've thought of cross breeding KBX and Orange Minsk, but I haven't done it. I usually plant them almost side by side with the thought that an accidental cross may occur but if it has, it hasn't been obvious in any successive generations.

I've always believed cat facing on the orange minsk is a result of cold temps while blooming, but since my KBX and Orange Minsk always grow under identical conditions within feet of each other, I'm beginning to believe a genetic factor is involved causing the Orange Minsk to be susceptible to the colder temps while the KBX isn't.

Based on the genetic influences stated and how they influence the resulting plants, I don't perceive a genetic difference between seed from an ugly, deformed tomato and a beautiful, perfect tomato. I know outside influences like viruses and other pathogens which may cause differences in the next generation of plants and fruit must be eliminated, If all seed is viable and pathogen free, shouldn't ugly fruit seed produce the same plant and fruit as pretty fruit seed?

While I'm not totally into the epigenetics concept, I am like Joseph a pragmatist and tend to save seed from the most perfect fruits. I do it because it seems the best thing to do in my "common sense" mind, not in my minimal "scientific" mind.

Ted

[drew51]

I think saving seed from perfect fruits, or large fruits makes sense as the seeds have the perfect environment to grow., Not that the DNA would be different, but you might get better germination or longer term storage as seed was produced under optimal conditions. If you grow 100 Minsk(e) and harvest seeds from the plant with the best looking fruit you are selecting for the plant, not the fruit, and could get a better looking fruit that way.
I have only been growing tomatoes for a few years. The only orange I have grown is Amana Orange, and it was super impressive, and you guys are saying Kellogg's, KBX, and Orange Minsk are better!? In that order? Wow, well that would be something. I think I will grow them in that order. No orange this year, next year I'll grow Kellogg's...

I grow Merizol Purple most years as one of my favorites. I usually plant about twenty seeds of every variety I plan on growing. I eliminate the weakest, slowest germinating plants eventually retaining the six best plants. I typically plant either three or four of the six plants giving the remaining plants away for someone else to grow.

A few years ago, I planted four Merizol Purple plants and gave the remaining two plants to a friend. My plants were killed by a late frost so I planted some purchased plants in the spots where the dead MP plants had been growing.

My friend planted his MP plants about two weeks after I planted mine and they survived and produced well. My friend harvested the best MP tomatoes for consumption. The small damaged fruits, he allowed to rot on the vine and drop to the ground. When I was planning my garden for the following year, I realized I had no MP seed remaining. My friends garden was pretty much dead in late summer, but I rescued the dried husks of the imperfect or damaged MP tomatoes from the soil beneath my friends dead plants. Those seed produced some great tomatoes this past summer and have also produced the plants for the coming season.

The only point I am making is some really great tomatoes can be produced from a lousy seed production by using plant selection instead of tomato selection.

KBX is the potato leaf version of Kellogg's Breakfast having been harvested from a field of Kellogg's breakfast. Some people say they are equal in all aspects except leaf form. In my garden, and I emphasize "in my garden", KBX is much better in all respects. I don't even grow Kellogg's Breakfast any longer. I suspect, but can't prove the PL leaf form makes a significant difference in plant growth and fruit production and taste.
Ted

"When ted asked originally about selectively breeding beauty pagent winners, I compared this to size, because beauty may be different in his eyes than mine. It is best when trying to breed something, that it be defined to make the scope of the work manageable ... in other words directed to a specific goal, or things will get even more ambiguous and progress harder to measure. But it definitely keeps life interesting and I'm sure has resulted in many nice heirlooms, evn if they were by accident!"

Tomato beauty in my eyes and mind means general uniformity in size with one slice being able to cover a BLT. It also means uniformity in color when ripe without green shoulders and little too no core. It needs to be resistant to cracks both horizontally and vertically after a small rain event. Some varieties seem more resistant to BER and blossom end dimples adding to their attractiveness or beauty. KBX, Limbaughs Potato Top, Prudens Purple, Dester, Stump Of The World, Wes (I'm not really a heart fan), and a few other varieties come close to my ideal every year. I'm not really a fan of almost seedless tomatoes because that usually means small locules with almost no gel. I believe the seed containing gel in the locules is where most of a tomatoes flavor resides. That would constitute "beauty pageant" beauty in tomatoes for me.

Ted