Heirloom susceptibility to disease?

[Seth Williamson]

I mentioned on another (non-gardening) list that I had started a bunch of heirloom tomatoes. I got this response:

"With specific respect to heirloom tomato varieties, the down side is the propagation of diseases. Most of those were replaced with disease resistant types a few decades ago. The current trend to return to the so called heirloom varieties has reinvigorated the diseases. Tomatoes of any variety that have been treated with copper sulfate to ward off the diseases renders the fruit questionable at best."

I am familiar with the general charge, of course. My own experience is that my heirloom tomatoes have done as well as any of the hybrids I've planted. I seem to remember that Carolyn says in her book that the danger is exaggerated.

On the other hand, maybe I'm missing some new trend. I'd hate to see a recrudescence of old diseases. Can anybody comment on this matter?

Seth Williamson

[Tom C zone 4/5]

I have been told time and again by *experts* that, "it is impossible to save OP tomato seed by home gardeners."

On at least two occasions by people eating OP tomatoes of seed I had saved.

Likewise the *what experts know*, of disease suseptibility of OP tomato is IMO, similarly untested and just plain blovation.

I did garden through and underwent a crop failure in '09 in NH of late blight. As did most every body else, OP or F1 hybrid growers alike in the north east.

My contempt of Master Gardener programs has grown, rather than abated over the years.

[organichris]

I've only had a problem with diseases one time - and that was with Black Krim. I know other have had issues, but to limit the issues to heirlooms is sort of stupid. I'd be willing to guarantee there is no sound proof heirlooms are bringing back diseases. Sounds like poppycock to me.

[Suze]

My observations throughout the years are that for the most part, tomatoes are tomatoes.

It is my opinion and experience that the sort of advice that suggests there are "special" disease problems with heirlooms in general (actually I prefer the term OP/open-pollinated, but that's a topic for another post), tends to come from folks who simply don't know what they are talking about and/or are merely (and inaccurately) repeating what they read or heard somewhere.

Now, I am not saying that there is no such thing as general hybrid vigor or heterosis when it comes to tomatoes. I have experienced it before in my own garden to some extent, but I have also seen plenty of F1 hybrids go down to or suffer from the same diseases that the other "heirlooms" in my garden did.

What most folks have problems with is foliar fungal disease (early blight and sometimes septoria - or edit/add - late blight). For the most part, there are not that many varieties (OP or hybrid) that show any significant tolerance to foliar fungal disease.

Of course, a few gardeners might have problems with fusarium (F), verticillium (V), RKN (N), which are all soil-borne, and can in fact choose to grow hybrid varieties that have those "letters" after them if they do in fact have those particular known problems. However - a "V" hybrid variety or "VFN" etc, certainly does not guarantee a completely trouble-free garden for anyone, even if your garden has any of those problems anyway. Tolerance =/= total resistance.

Gardening is like life - you gotta regularly do stuff to keep things going, and some years are better than others no matter what you do.

[feldon30]

Originally Posted by Seth Williamson

I mentioned on another (non-gardening) list that I had started a bunch of heirloom tomatoes. I got this response:

"With specific respect to heirloom tomato varieties, the down side is the propagation of diseases. Most of those were replaced with disease resistant types a few decades ago. The current trend to return to the so called heirloom varieties has reinvigorated the diseases. Tomatoes of any variety that have been treated with copper sulfate to ward off the diseases renders the fruit questionable at best."

Can anybody comment on this matter?

I have a brief comment:

The person who gave you this "advice" is an idiot.

Modern tomatoes were selected not so much for disease tolerance/resistance, but to be perfectly red, uniformly round, all harvested in a narrow time window, with thick skins in order to stand up to long distance shipping, refrigeration, and proper consistent coloration once they are sent to the Ethylene gas chamber en route to the grocery store for further refrigeration and abuse.

Not every hybrid is disease tolerant, just as not every heirloom is a flavor blockbuster. I would have absolutely no objection to crossing tasty tomato varieties with hybrids to introduce disease tolerances, as long as the flavor and variety isn't lost. I just don't know anyone who is doing this commercially because there's no money in it.

Further, there have been a lot of breakthroughs in organic treatments and solutions in the last 10 years that make fusarium, nematodes, alternaria, early blight, etc. manageable. Whenever someone trots out the copper sulfate, I know I'm talking to someone who is about 20 years out of date on tomato cultivation.

[TZ-OH6]

A crop that is not resistant will not reinvigorate a disease, it will tend to weaken it (in theory). The resistant plants are the ones that select for more robust forms of the disease. Just think about the super germs found in hospitals. The diseases are still present in fields full of disease resistant hybrids. The modification to the plants simply allows the 'resistant hybrids' to hold on long enough for a profitable harvest, but the plants are still infected and propagating the disease organisms.


Most of the diseases copper sulfate is used for (foliar fungal diseases) are are not the diseases bred into modern hybrids, so there is little arguement there. You have to know what disease ails your garden (if any) and pick a specific hybrid to deal with it. That tosses water on most people saying 'I grow hybrids to avoid diseases' (well, what diseases are giving you problems?......)

The hybrids are better than heirlooms arguement holds up for commercial growers needing to make the most profit from fruit destined for tomato paste and MacDonald's burger slices, but not for the backyard gardener in most cases.


I do have a couple of spots where Fusarrium or Verticilium hits plants every year, and if it spreads, I may have to switch to growing specific hybrids, but someone has been growing tomatoes in this dirt for 30 years and we have not NEEDED to grow hybrids in all that time.

[feldon30]

I think there are more options for Fusarium and Verticillium besides fumigation now.

[Wi-sunflower]

Another comeback to the disease question is -- where do you think they find the disease resistance in the first place ??? from those old time varieties that showed the resistance LOL.

It's just like with the potatoes, they have to go back to the closer to wild (read un-hybridized) varieties to find the genetics.

Carolyn had a great post on an old forum about this. If I can find my copy of it on my old computer, I'll post it later. I had a computer meltdown about a month ago and I'm still trying to find things I need so be patient with me.

Maybe Carolyn will see this and post her take on this issue.

Carol

[Dewayne mater]

Relative to the others who have responded I'm not qualified to comment, but, that never stopped me before! So far I've had the fun to grow only about 30 varieties of tomatoes some hybrid, mostly heirloom. In my tiny corner of the world, Indian Stripe has shown a natural ability to resist foliar diseases significantly more than any other variety, heirloom or hybrid. Other varieties have also shown varying degrees of resistance, relative to the varieties being grown around them.

My junior sleuth conclusion is that some varieties do have some disease resistances in certain circumstances and therefore it is likely their are other varieties that show resistance too, both in my circumstances and others. This is probably because certain varieties are better suited for specific geographical areas because they were selected by good gardeners through generations as the plants doing the best in the area.

That said, so far in my experience, every tomato plan eventually succumbs to something and resistance is generally just an extension of the life of the plant for probably for a few weeks at most.

[BlackestKrim]

What are the options for verticillium and Fusarium now, btw?

Southern Exposure SE has some ratings on certain heirloom's disease tolerances. I'm sure we have also noticed certain heirloom cultivars showing particular resistances to certain diseases.

I think the trouble is that to know that a variety is definitely resistant, you would need a fairly broad scientific study. A large number of plants, along with controls, with a certain amount of the pernicious agent introduced evenly. Just saying "I noticed my KBX doesnt die of blight when others next to it get it" isn't enough to definitively say that KBX is blight-resistant. Since it is not economically feasible to do these studies for heirloom varieties, people just assume they have no resistance to that disease.

As far as breeding resistance into plants, I read that for some cucurbits, they found that a specific gene cluster was responsible for increased powdery mildew resistance. If resistance can be attributed to a particular gene or small gene cluster, I'd imagine (not being in any way a geneticist) that one could easily cross that plant with an heirloom and select out a resistant OP with desirable characteristics.
I know genetics can get much messier than that however. Some traits can be spread over many gene groups and can be hard to breed for. Excuse me if I mangle the science, I am an engineer, not a biologist.

If genetic engineering were cheaper and easier, we could just pluck out the gene that gives resistance, plunk it down in our Black Krim, and not worry about getting all the other characteristics all messed up! Unfortunately that science is not attainable for the home grower now.

[carolyn137]

I am familiar with the general charge, of course. My own experience is that my heirloom tomatoes have done as well as any of the hybrids I've planted. I seem to remember that Carolyn says in her book that the danger is exaggerated.

*****

I'm not sure I used the word danger although I've certainly said that most OP's do as well as hybrids when it comes to disease and that was mentioned above by someone, the reason being that THE most common diseases of tomatoes are the foliage diseases and hybrids aside, with few exceptions there are no genes that have been IDed that impart strong tolerance to the foliage diseases.

Suze, Feldon, TZ and others have said about the same as I would have written.

Just a couple of points.

If OP's, heirloom or otherwise, were so susceptible to diseases we wouldn't have all the Livingston varieties, the Henderson varieties, even Trophy from what, 1860, Green Gage and Roi Umberto and the small red and yellow pears, all pre-1800 varieties, with us today. And I'm leaving out lots of other seed companies that were responsible for introducing some wonderfuol varieties from the late 1800's to maybe 1930 or so.

The genes for many tolerances incorporated into the newer hybrids came not from our garden tomato, rather, from some of the other species and Keith Mueller has noted those at his website.

As mentioned above, and I'll kind of repeat it, hybrids were never developed specifically for the hobby gardener, they were developed for the commercial farmers, except for more recent varieties such as Brandy Boy and Glory and I think there are a couple more for the home gardener.

Carol, I can't remember which article you're talking about unless it was the one I wrote that was published in National Gardening when it was still alive and well. It's still available and I have it in my faves somewhere b'c when they went under due to the parent Co going bankrupt they chose certain articles and asked permission to put them as links at their new sites and I think paid each of us $25 for that permission. I spent that ASAP.

Some of the greatest satisfaction I've had when it comes to tomato diseases has been working with the Cornell Coop extension in the two counties where I've lived and gardened. Most specifically when I was growing at the old family farm and the head of the five county area around Albany, NY, wanted to do a disease survey comparing diseases between OP's and hybrids, so I breathed deeply and planted some hybrids. They had student interns that were supervised doing the Iding, with supervision, and recording the data. The head of that Coop Ext, Dale Riggs, had learned about Iding diseases from Dr. Tom Zitter at Cornell who is a tomato disease infection specialist and I learned more from that summer's growouts than I ever knew before in terms of IDing diseases, most of whch were foliage diseases b'c aside from a bit of random Verticillium there aren't that many soilborne diseases where I live and garden.

OK, typed too much, but I agree that there are still lots of folks out there who have no idea what they're talking about, didn't Feldon say idiots? So that's why it was so satifying to me to speak to garden club members and at Master Gardener classes and hold field demo days as well as presenting info to farmers wanting to get into the heirloom tomato business, this via the Cornell Coop Ext, so that some of the ignorance could be lesseened by actually seeing compariosns of OP's and hybrids.

[BlackestKrim]

I found this link concerning the genes for disease resistances in tomatoes, including heirlooms. Looks like he has been sequencing DNA for many different tomato varieties to find whether they have the known gene for resistance to a certain disease:
http://tgc.ifas.ufl.edu/2009/Shi%20SNP%20Multiplex.pdf

I'll have to wait until the boyfriend gets home to interpret this, as he's the computational biologist and I am just flailing around in gnorance of biology.
For example, page 18 seems to say that Riesentraube has the gene for verticilum race 1 resistance while page 24 says "susceptible to all." Or is "gene reported" the "official" resistance?
I can't find any published reports on this, but at least someone is working on it. They say they will have the "real tests" this summer.

EDIT:
had it explained over lunch. He developed a quick, comparatively cheap genetic test for resistances. (Lower case indicates lack of the function. Mi: root knot nematode resistance, mi: doesnt have teh resistane.) Some varieties are known to have resistances(BHN-444) and some don't (Riesentraube) and those were used to determine which nucleotides could be used as markers. pages 21-25 show results of this testing.

The developer of this method will use it to make heirloom-quality hybrids that are resistant. This is good- that means that if we have a spot of garden with fusarium, we can grow such varieties there. (I think one can use grafted heirlooms, too.) Another possible benefit is if this is picked up by growers- then perhaps we can have more "real" tomatoes in super markets.

Anyways, it is a cool bit of biotech. I am sure that there are quick disease tests that have been developed, but they are likely proprietary and held by major plant breeding companies.

The diseases that matter to me are typically foliar, like blight, so resistance to these doesn't affect me either way.

[carolyn137]

Carolyn had a great post on an old forum about this. If I can find my copy of it on my old computer, I'll post it later. I had a computer meltdown about a month ago and I'm still trying to find things I need so be patient with me.

****

Carol, I tried answering you much earlier this AM but there was a server error and I lost the whole post.

I know what you're referring to now.

When I first started posting online about tomatoes it was at the AOL TOmato Forum in the mid to late 80's and I wrote a series of articles about foliage diseases, soilborne diseases, those diseases that have wilting, BER and many more articles.

When I was asked to be the lead Moderator at Tomatomania when that site first opened there were some folks who knew of those articles and I was asked to post them as a link in their resource area, which I did.

I was surprised to find that some of them showed up at other sites including one University site, some Master Gardener sites and some others.

I was not happy about that at all.

In any case much info in those articles is quite out of date when it comes to possible prevention and treatment and in the meantime there have been several newer diseases recognized that have turned out to be a problem.

Most of the diseases have been a known problem for decades but new races of Fusarium and TMV and Verticillium, for instance, have been ided in the meantime.

[carolyn137]

EDIT:
had it explained over lunch. He developed a quick, comparatively cheap genetic test for resistances. (Lower case indicates lack of the function. Mi: root knot nematode resistance, mi: doesnt have teh resistane.) Some varieties are known to have resistances(BHN-444) and some don't (Riesentraube) and those were used to determine which nucleotides could be used as markers. pages 21-25 show results of this testing.

The developer of this method will use it to make heirloom-quality hybrids that are resistant. This is good- that means that if we have a spot of garden with fusarium, we can grow such varieties there. (I think one can use grafted heirlooms, too.) Another possible benefit is if this is picked up by growers- then perhaps we can have more "real" tomatoes in super markets.

Anyways, it is a cool bit of biotech. I am sure that there are quick disease tests that have been developed, but they are likely proprietary and held by major plant breeding companies.

The diseases that matter to me are typically foliar, like blight, so resistance to these doesn't affect me either way.

*****

What's important is not jsut Iding the nucletides involved with Septoria, b'c with the other ones you mentionmed the genes are already known and used, but actually isolating any genes found for Septoria tolerance.

And even that isn't enough if we use the example of Early Blight b'c while genes are known for that thyey're low level so aren't much help.

There are several groups I know of who are working on finding the actual gene(s) involved with Septoria to be able to use it (them) if it ( they) turn out to be high level and useful.

But about the Fusarium you referred to, yes, growing F tolerant plants is OK as long as one knows which races are present in the area where they grow b'c there's no cross tolerance, but again, whether it's with grafted plants or with F1 hybrids that have the relevant genes it only means a week or two more of plant life, which as a few mentioned above, including me, are of use only for large scale commercial farmers.

heck, if all varieties were tolerant to everything out there we wouldn't have so much fun trying to ID tomato diseases at message sites such as this one.

Some will say that this or that OP variety is tolerant to this or that pathogen but that really depends on the presence of the pathogen in any given season and the level of that pathogen in the environment.

All F1 hybrids that have alphabet letters next to their names have to be challenge tested in an approved lab with the relevant pathogens under controlled conditions, with controls, before they can be so approved to list those tolerances.

[puttgirl]

Carolyn, I wish you'd speak to our MG's!
I must admit though, that some of our MG's are coming around! Most of them are even advocating "no-till" gardens!