Your premise is incorrect.

The reason to graft tomatoes is solely to take advantage of something like disease tolerance which the rootstock has but the scion does not. It is irrelevant whether the varieties are 'related' in this context. If you were grafting tomato onto eggplant as an example, then you might want to know a great deal more about parents because of incompatibility issues.

Regardless, Big Beef's parents are not publicly known.

DarJones

fusion

I read that information here. Francis said that when it comes to rootstock breeding, the key to hybrid vigor rests with the parents selected for crossing.

"The further away in genetic relationship the parents are, the more vigorous the plants tend to be," said Francis. "That is, two cultivated plants with similar genetic backgrounds will be less vigorous than a cultivated plant crossed to a wild species." In fact, the three rootstocks that performed the best were all crosses between a wild South American species and a domesticated tomato.

But if the parents of Big Beef are not known, it doesn't matter.

I was wrong -- apparently the researchers meant that the parents of the hybrid or crossed rootstock should not be related to provide the strongest rootstock, not a stronger result of the graft.

I misunderstood, thinking they meant that the grafted scion would be stronger if it was unrelated to the rootstock or its parents.

I know David Francis and was referred to him by someone with the SOLcap program. My role was to send good tasting heirloom varieties for inclusion in development of hybrids.

But we also talked grafting and at the time with what they'd been doing he felt that for most home growers Celebrity was just as good as fooling around with Beaufort or Maxifort or the Japanese ones.

It escapes me WHY some folks think that grafting tomatoes makes a huge difference, it really does. As one of our Australian friends said once....and selling grafted plants in that country is common.....it just lets them charge a higher price for a plant.

Carolyn, and Anney, if you go to the NCSU Cultivar list you'll see that NO parents are listed for any hybrids. It's a very competitive field and parental inputs, b'c with modern hybrids there can be up to 4 genetic inputs in each breeding line such that there can be 8 parental inputs in the final hybrid. On'ly the earliest ones bred such as Ramapo F1 and a few others are the parents, only two, known.

Carolyn

It's my understanding that tomato grafting is practiced to enhance or increase the production of heirloom or open-pollinated tomatoes by introducing foliage disease resistance or tolerance by the rootstock to the scion. The link below is one of many that describes the value of grafting tomatoes that is being practiced in many parts of the world.

From all that I can find about the diseases that have infected my tomatoes pretty severely (Early Blight and Septoria), no tomatoes are listed as being tolerant of Septoria at all (though I believe researchers are working on it), but a few are listed as being tolerant of Early Blight. So if there's a chance I can avoid the worst of Early Blight next year by grafting a wonderful-tasting but vulnerable to disease-heirloom to a disease-tolerant rootstock, I'll try it.

To repeat, what I want to do is see if the heirlooms or open-pollinated tomatoes that are vulnerable to foliage diseases in my garden can be grafted to a disease-tolerant rootstock to avoid the worst of the diseases.

I'm really getting tired of starting tomatoes and putting in all that time and effort year after year, only to have them die in mid- or late-July due to Septoria and/or Early Blight.

Despite all my spraying and diseased leaf-removal, I cannot keep ahead of these two diseases. And for all I know, my plants may have been infected with other diseases -- the South has a lot of them that infect tomatoes when the weather is hot and humid.

It will be flying blind for the most part, and I think I'll start with only one heirloom next year, probably a Brandywine or maybe an Opalka, using the most disease- and heat-tolerant hybrid I can identify as the rootstock. Big Beef is one of the most disease-tolerant tomatoes according to many reports. It's also relatively heat-tolerant, though there are others that are listed as being developed for growing in Southern heat.

My Brandywine gave up the ghost to disease pretty quickly, the Opalka more slowly. The Goose Creeks (red) are STILL green and healthy and productive, even though they were surrounded by diseased plants, so I think I'll grow the GCs again next year to see if that characteristic is just a fluke this year or if it's going to be a reliably disease-tolerant tomato in my environment.

Here is a link that might be useful: Grafting Tomatoes to Manage Soilborne Diseases and Improve Yield in Organic Production Systems

Anney, clicking on your link, which I've tried three separate times now, stops my computer. I wanted to read it before I answered you, but can't.

Carolyn

Morning, Carolyn!

Sorry about that hanging link! It's a PDF file so maybe that's what's holding it up on your computer. Here's a summary of the paper. And here is the title presented as several search links, though they all appear to be in the PDF format. But maybe you'll be able to access one of them.

Here is the paper in another format. It's more than 100 pages long.

Grafting heirlooms to strong disease-resistant rootstocks does NOT prevent diseases which may reside in the soil but are also wind- and rain-borne. Those spores fall upon the strongest plants as well as the weakest plants and may infect them with diseases.

But what grafting with a disease-resistant rootstock does, if I'm reading correctly, is give vigor to the scion, the heirloom that is nearly 100% vulnerable to such diseases, so that it is better able to withstand disease pressures, even of diseases that the rootstock does not have tolerance for.

Bella Rosa Hybrid Tomato (VFFAStTSWV) [as well as Big Beef Hybrid (VFFNTASt)] is recommended on some sites as a good rootstock since it has tolerance to so many diseases. Neither of these hybrids has tolerance for Septoria OR Early Blight listed, though the resulting plants when grown with them as rootstocks are claimed to be tolerant to both diseases.

We'll see...

Anney,

You are still on the wrong track. Totally wrong.

If you read that paper carefully, you will see that it is advocating grafting as a method to control SOIL BORNE diseases. It is totally ineffective at controlling foliage diseases like Septoria.

The good news is that there are a few - very few - septoria tolerant varieties available today. Burgundy Traveler and Eva Purple Ball are two that are consistently tolerant in my garden. This is a low level of tolerance. When disease pressure is high, they still are hit hard but usually not until they have produced a crop and several weeks after most other varieties are long gone.

I'll see if Keith Mueller can post a reply re why it is difficult to incorporate septoria tolerance into tomatoes.

DarJones

Keith is not feeling well tonight so I will post a few more items re this problem.

1. Septoria tolerance is present in Solanum Lycopersicum in a very mild and easily overcome version. It is almost totally ineffective in some places such as Brazil where the local strain of Septoria has totally overwhelmed the resistance of this gene. Septoria tolerance can be found in some S. Lycopersicum breeding stock available from TGRC such as LA1800 and LA3126 but this is just the easily overcome version.

2. Septoria tolerance in a much stronger version is found in the Solanum Peruvianum complex. TGRC LA2744 is one variety that has a significant and effective gene. Unfortunately, crosses between peruvianum and domestic tomato are very difficult to nearly impossible to make.

3. Some researchers are already working on this issue by bringing in serious breeding efforts to work genes over from the resistant wild species into domestic tomato. You can find quite a bit of work by Martha Mutschler with a google search.

4. There is still some benefit to grafting an heirloom onto a vigorous rootstock. This is because a good rootstock will push the heirloom scion to grow faster. It is well known that a fast growing tomato can to some extent grow out of the effects of Septoria. What happens is that Septoria spreads rapidly when weather conditions are favorable with high temps and high humidity, but when the sun shines and humidity is low, the plant can grow rapidly enough to replace much of the diseased foliage.

5. Breeding for Septoria tolerance is a long term project. It will take several years to bring in the genes from wild species and will be a much longer time before a stable OP variety with desirable fruit characteristics can be bred. Note that you can breed the tolerance gene from Eva Purple Ball into Brandywine in just a few generations. But that gene is easily overcome. The hard work will be bringing a really strong gene in and incorporating it into a good flavored tomato.

DarJones

fusion

No, I'm not totally on the wrong track, but it must be time for me to leave GardenWeb if my posts are so unclear. From an earlier post in this same thread: From all that I can find about the diseases that have infected my tomatoes pretty severely (Early Blight and Septoria), no tomatoes are listed as being tolerant of Septoria at all (though I believe researchers are working on it), but a few are listed as being tolerant of Early Blight. So if there's a chance I can avoid the worst of Early Blight next year by grafting a wonderful-tasting but vulnerable to disease-heirloom to a disease-tolerant rootstock, I'll try it.<?blockquote>

Anney, Please don't leave gardenweb. I'm not posting to upset you.

Take a deep breath and consider that you know more about tomato diseases than most people will every try to learn.

My point with the above is only that grafting does not significantly affect tolerance to Septoria or Early Blight. Give it a try. I did and found that grafting Little Lucky onto a vigorous disease tolerant rootstock gave me a much better crop of tomatoes. But the vine still got septoria.

DarJones

Anney, please don't be upset. If you check out the rootstocks Maxifort and BEaufort and I forget the names of the ones from Japan you'll see that none of them have any resistance OR tolerance to common foliage pathogens as part of their genetic makeup.

So it's only by individuals saying that this or that variety is tolerant to this or that foliage disease that we have to go by. And even that isn't that helpful b'c the spore burden for Septoria can vary widely in different parts of the country and even within counties in a given state, etc.

Infection is dose dependent .

There are two professional hybridizers who are currently working on Septoria, and Keith knows who they are as I do. I was asked by one of them to find some folks who did have Septoria problems, and that's Dr. Randy Gardner, Hoosier directed me to another person, I put the two together and it's been very beneficial b/c it turns out they knew folks in common.

Keith got his MS degree with Dr. Gardner and Randy did contact Keith about it so Keith knows about this as well.

So fingers crossed that down the road there will be some major developments,

In the meantime, you can swallow deeply and consider protecting your plants with Daconil. I switched to growing organically in about 1999 but when faced with the recent Late Blight problems here I had a choice and that choice was to hopefully have tomatoes, or not. Daconil is a very effective at preventing fungal foliage diseases as well, but is best used preventativly, not as a cure.

I don't want to get into Daconil in this thread, far from it, but I've researched it for years and I'm comfortable using it.

I Don't give one whit if a product is "organic" or not b'c what concerns me is toxicity to humans, pets, bees, and the environment in general. And Rotenone, approved by almost all organic certifying agencies, has a slightly higher toxicity than does Daconil, the most widely used ant-fungal in the world and ahs been for almost 30 years now, so more information about it is known than almost any other product.

Carolyn