From

Location

Message

Date Posted

Bowdon, GA

This is my first year growing tomatoes. I plant lots of seeds other growers have sent me in the past. I can see what Marv has been talking about. All the seeds had a name and a number no indication of variety on most. Out of the 8 plants I put in the ground I had at least 3 obviously different types. One is even a potato leaf type. Even though the seed was from a big tomato it is much smaller than the other two varities given the same care.

8/19/2014 11:28:26 PM

Bowdon, GA

Carolina cross is the only melon that will grow 200lbs an ag is the only pumpkin that will get a 1000 so its ok to assume the variety. There are obviously many types of tomatoes that will grow big tomatoes. But I'm in the same boat as most of the growers. After several generations with no name attached is it too late to start now? Will they eventually homogenize in to one type?

8/19/2014 11:33:55 PM

East Carbon, Utah

No, they will not homogenize into one type. In contrast to pumpkin growers, very few tomato growers routinely make crosses among their giants. Perhaps 95+ percent of the Big Zacs submitted here can be traced back to a single tomato:

Big Zac (F2 presumed) (4.59 Lyons 2006)

Though Big Zac is officially a hybrid, selective breeding and hundreds of tomatoes grown and submitted to various contests has resulted in a Big Zac open-pollinated version that has more genetic variability than a typical heirloom. However, these Big Zac specimens represent only a fraction of the potential genetic diversity for growing big tomatoes.

Delicious and MegaMarv are more true-breeding open-pollinated/heirloom varieties with distinctly different traits than Big Zac (OP). These three varieties account for the vast majority of the giant tomatoes which are submitted at weighoffs.

Yet there are literally dozens of other varieties with potential, with genetic traits which could be infused into the gene pool of giant tomatoes to increase the chances of producing very large tomatoes.

Brutus Magnum
Belmonte
Bezrazmernyi
Church
Severnyi
1884
Domingo
Terhune
Michael's Portuguese Monster
Porterhouse
King Kong
Bolshaya Devochka
Gildo Pietroboni
Hoy
Chilo della Garfagnana
Rebecca Sebastian's Bull Bag
Gold Medal
West Virginia Sweet Meat
Shuntukski Velikan
Sumo
Joe's Portuguese
Olena Ukrainian

And many more varieties, in the right hands and under excellent growing conditions could (and in many cases have) produce(d) 4+ pound tomatoes. If crossed with varieties with the genetic trait to produce lots of megablooms, 6-8+ lb. tomatoes could perhaps be routine in just a few years.

8/20/2014 1:40:49 AM

East Carbon, Utah

In my opinion, the primary reason that a new pumpkin world record is set almost every year is because hundreds of dedicated growers around the world make the crucial crosses to keep genetic diversity high and vibrant. "Hybrid Vigor" is crucial in any breeding program, plant or animal, if serious improvements are to be made.

Tomato growing, on the other hand, is plagued with "Inbreeding Depression". Since the gene pool is so limited, it becomes a contest of who is the most dedicated and implements the best growing techiques.

Genetic mutations are so rare that simply selecting seeds from the biggest specimen every year of a pure-breeding variety will do little to improve the line. There needs to be a continuing supply of fresh genetic material with which to work or that barrier will continue to seem insurmountable.

28 years and counting...

Just my 2 cents worth.

8/20/2014 1:42:04 AM

Allentown, PA

Dale,

You are a wealth of knowledge and I'm extremely pleased you are with us here.

8/20/2014 7:24:51 AM

Bethlehem CT

Seamsfaster I agree with everything you said. I might have chosen a different word than inbreeding depression, because tomatoes don't exhibit inbreeding depression in the same way a crop like corn or other crops do. I agree however that the hybridizing and genetic shuffling may be necessary to bring out some of the size genetics that are latent in our seeds. Their is so much diversity in the tomato, just look at a Baker Creek catalog or Sand Hill preservation Center catalog. There are dozens of cultivars that can way 2-3 pounds or more.

8/20/2014 7:46:37 AM

Bethlehem CT

ooops! meant to spell "weigh" 2-3 pounds.

8/20/2014 7:47:40 AM

On top of Brush Mountain, Pa.

I am in agreement with Seamsfaster completely. I have been "putting it out there" for a good while that recording the history of the seeds is essential. And we should be crossing more of the "more special" tomatoes but if good records are not kept the confusion will become only worse. Pumpkin growers have done a great job of keeping track of their various crosses and laying them out in the seed name. Making tomato crosses is a bit harder to pull off. Sometimes there is not enough pollen as it is either stuck together in wet weather or less viable if it is too hot or too cold or too whatever. Since tomatoes self pollinate and pumpkins don't there is that complication as well. Timing in tomato pollination is critical for a successful cross. I could go on. Bottom line is that to make the various crosses of tomatoes will take growers willing to learn how who also are very patient and who also keep good records. Sadly, there may not be enough of those people. But then again, maybe the few there are can create some of these seeds but what is the use really if growers don't name them properly farther down the chain? Definitely an uphill battle! Seamsfaster may be the one to lead it.

8/20/2014 10:50:18 AM

East Carbon, Utah

I've attempted about 60 crosses so far this year with about 15% success rate. As you say, Marv, temperature makes a HUGE difference. We've had a cool spell recently and I couldn't believe how much pollen came out of the blossoms this morning! In contrast, most days I could easily count the pollen grains, if any, that came from otherwise healthy looking blossoms.

I'm a total beginner at this tomato crossing process so have a lot yet to learn. But the procedure itself is really not so difficult and takes little more time than crossing pumpkins.

8/21/2014 1:34:13 AM

East Carbon, Utah

Consider for a moment some of the traits which might contribute to a 10-pound tomato:

• Very thick pedicle and peduncle
• Very thick main stem
• Massive root system
• Roots resistant to disease and attach by tiny critters & microbes
• Ability to absorb and transport large quantities of water and minerals
• Ability to deposit a high percentage of water and nutrients into a growing tomato
• Ability of fruits to expand rapidly without splitting
• Production of massive megablooms - 8-10 full-sized, fused ovaries, for example
• Leaf surfaces exceptionally efficient at extracting CO2 from the atmosphere
• All stages of photosynthesis extremely efficient
• Fruits that grow for 60-70 days before starting to ripen, vs. 40 or so.

And so on. It's very unlikely that any variety grown today has all the potential giant-producing traits collected in a single genome. Thus the need for cross-breeding.

Many of these traits are mediated at the subcellular level - plant hormones, enzymes, cell wall components, etc. - that are not obvious to the human eye. Though the Tomato Genome Project has been completed for a couple of years now, I'm not sure even the expert geneticists can yet say a lot, definitively, about which specific genes might contribute which positive traits to growing giant tomatoes.

We are still years away, I think, from being so high-tech that genetic engineers would be involved in the sport on a regular basis. So old-fashioned cross-breeding is where we're at for now.

8/21/2014 1:35:50 AM

On top of Brush Mountain, Pa.

I think with tomatoes it will be only a few people who are involved in creating new crosses. The rest of the people will be growing them out and hopefully reporting back. This will take longer than with pumpkins. I will have maybe two crosses that could be worthwhile for this next season that would be worth growing out. One of these is not even mine. Minnie Z has been growing out a triple cross she made 4 years or so ago which involved Big Zac and one other and she has agreed to send me a few seeds and I was able to cross Hunt's strain of Delicious and Megamarv though I don't know how many seeds I will have as the tomato is still growing. Minnie believes her new seed which is now an F4 or F5 has promise. Looking to next year. Pumpkin crosses have not been made scientifically based on genetic information and they have increased size so maybe tomato growers can as well.

8/21/2014 9:21:11 AM

Cameron

Hey Marv, your cross looks interesting. I would be interested in trying it. Let me know if you get enough seeds to pass along to few growers to try out. Thanks.
Jane & Phil

8/21/2014 9:53:44 AM

On top of Brush Mountain, Pa.

Will do.

8/21/2014 11:22:33 AM

Central NY

I would be interested also Marv .... To report back.... Then eat...

8/21/2014 12:22:56 PM

On top of Brush Mountain, Pa.

Too soon for me to know what seeds I might have available at end of season. The tomatoes are still growing and not yet mature enough to have any seeds.

8/21/2014 4:58:21 PM

Bloomington, IN USA

I have to take exception to what had been stated about the genetic diversity of tomatoes.
Sure we have plants with varying leaf shapes & size & color of fruit.
But genetically speaking, the tomato genome is quite narrow, especially if you compare it to many other plants.
There was a genetic bottleneck when the tomato was taken to Europe from South America & it persists today even with the introgression of genes for disease resistance.
I think it makes sense to try to make crosses among the varieties such as Big Zac, Delicious, MegaMarv & Brutus Magnum which are proven to produce megablooms & very large fruit.
On the other hand, it is fairly likely that these varieties genetically speaking are not that different, so it is perhaps more likely that bringing in some genetic material from more diverse places such as Russia, Eastern Europe or Australia could bring in more genes that would help bolster some of the traits that Dale mentioned.
I would be interested in helping out with such a project to the extent that I could.

8/21/2014 10:40:06 PM

Bowdon, GA

Few questions. How do you keep them from self pollinating at least some of the seeds? I have to agree that it is hard to make crosses when you don't even know what your crossing. Or should you just cross the seeds that are producing the best fruit?

8/22/2014 12:06:22 AM

Bowdon, GA

Which would be the best way to go. Sorry for a watermelon analogy but its what I know best. I had some seeds that were Mountain Hoosier x Carolina Cross. The first generation there were two different rind colors. They were selfed to see if the color of each would stick. The next generation there were about 6 color variations. So it would take several generations to straighten out the color. I'm assuming two different varieties of tomatoes would have similar results. Would it be better if you picked two seeds you knew the variety of and crossed them. Say you know both are Big Zac and you stick to only crossing the biggest that you know are Big Zac? Similar to what melon and pumpkin growers have done.

8/22/2014 12:16:30 AM

Bowdon, GA

Sorry if I sound ignorant but I really don't know much about tomatoes

8/22/2014 12:17:12 AM