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General Category => Nightshades => Plant Breeding => Tomatoes => Topic started by: Diane Whitehead on 2019-02-28, 07:12:37 PM

Title: Breeding for Late Blight Resistant Tomatoes
Post by: Diane Whitehead on 2019-02-28, 07:12:37 PM
We have had a long discussion on late blight, potatoes and tomatoes.

Instead of adding to it, I'd like to start this new one on a project to start breeding this year.

I have some resistant varieties, and have bought more, from England and the U.S.

 These are the seeds I have already grown. I don't know which resistance they have.

Geranium Kiss
Legend
Bolivianische Obsttomate
Chernomor, Reg Lf
IPK LYC 859 El Salvador
Little Julia
Matt's Wild Cherry
Sky Reacher
Skykomish

These are the new ones I just bought.

Make My Day - by Tom Wagner
Cocktail Crush a new release by Burpee Europe presumably F1, but it doesn't say
Crimson Crush F1
Oh Happy Day
Losetto Cherry F1  bred from the Bangor University research

The packets promise just 10 seeds each, but if someone has a project that they would be useful for, I can spare a few.

I hope Carol can suggest the best way to proceed.

Dehybridize the new European ones?  Start crossing?


Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Joseph Lofthouse on 2019-02-28, 09:05:11 PM

Link to the other thread: http://opensourceplantbreeding.org/forum/index.php?topic=58.0
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: reed on 2019-03-01, 03:43:34 AM
I got some Iron Lady and a hybrid called Celebrity to add in to my mix. Celebrity doesn't have blight resistance but resistance to about all other tomato diseases and since blight is just one of many problems in my neighborhood I need the others too.  I'm just gonna try to cross them up several others of my own and see what settles out. I'm using Mr. Stripey, one of my favorite old tomatoes that apparently already has some resistance to try to come up with something that tastes the way we like but keep producing till frost like in the old days.  Diseases are bad enough here that I don't have to do much except wait till healthier longer lived plants show up.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: ImGrimmer on 2019-03-10, 12:47:43 PM

Legend
Skykomish

didn`t show resistency here in northern Germany.

Mountain Magic has very good resistency.

I have my own tomato strain which shows often resistency but fails in some years between. But it has always better resistency than other varieties.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: nathanp on 2019-03-10, 02:56:18 PM
This is in the other post as well

I found the list:
Homozygous for Ph2 and Ph3
Iron Lady
Lizzano
Skykomish (from Tom Wagner)
Crimson Crush

Heterozygous for Ph2 and Ph3
Mountain Magic
Mountain Merit
Defiant
Jasper (probably has both - not confirmed, unsure if heterozygous or homozygous)

Homozygous for Ph3
Plum Regal

Homozygous for Ph2
Legend (OP)

Possibles/Probables
Matt's Wild Cherry - probably Ph3
JTO-545 - probably Ph2
Sun Gold   Some resistance anecdotally, but I am not sure what it is from.

These are the ones I have grown. I am currently working on growing out several of the F1 hybrids to stabilize the lines. Skykomish is F8/F9 so that is stable already, though a little too long season for my climate.

Homozygous for Ph2 and Ph3
Iron Lady
Skykomish (from Tom Wagner)

Heterozygous for Ph2 and Ph3
Defiant
Jasper (probably has both - not confirmed, unsure if heterozygous or homozygous)

Homozygous for Ph3
Plum Regal

This webpage has a more complete list
https://articles.extension.org/pages/72678/late-blight-management-in-tomato-with-resistant-varieties (https://articles.extension.org/pages/72678/late-blight-management-in-tomato-with-resistant-varieties)
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2019-03-10, 05:33:20 PM
Something that really strikes me about that list Nathan is that you have four varieties in the Homozygous Ph2 and Ph3 list. It seems you me that crossing up those varieties should be done and since many of them are F1s should lead to many new varieties.

My other thought is to develop a lot of F2 crosses with my favorite tomato germplasm. Then when the blight hits should have some resistant material with those traits. Course wouldn't wait for that but rather send some F2 seed out to collaborators.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2019-08-25, 11:04:36 AM
The one plant of Lizzano F2 I grew out is interesting. Would be good for winter breeding. Seems like it belongs in the very short season very small fruit and plant category. Saved some seeds.

Have an Iron Lady F1 in the seed saving pile. No sign of a ripe Skykomish yet. No crosses made.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: ImGrimmer on 2019-08-25, 02:21:51 PM
I grew many F2 and F3 Mountain Magic plants. So far no late blight infection. LB season just started. Today I found 2 infected plants in other strains.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2019-09-02, 09:42:51 PM
My one ripe Iron Lady didn't have many seeds. Then half sprouted while fermenting. So I have four Iron Lady F2 seeds drying. I may call that good. Picked some more and just put them in with the general bag to eat or give away. Still no Skykomish. Have to say, pretty excited about Lizzano comparatively for shortness of season. Saved lots of seeds. Would be a good addition to a variable population of short season stuff.

Lizzano X Big Hill would be interesting. Have to add that to my to do list...
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2020-02-16, 08:06:01 PM
Quote from: @snickeringbear" source="/post/7879/thread" timestamp="1422386101
Iron Lady is homozygous for early and late blight, but heterozygous for septoria.  IMO, the septoria tolerance is weak.  It goes down in my garden just as fast as most other tomatoes.  I'm not sure if this is because my garden is being hit with a different strain of septoria or if something else is going on.  Regardless, LA2175 S. Habrochaites is just about immune to all three diseases in my garden.  I have some F2 seed to grow out this year from a cross of LA2175 with Piennolo Del Vesuvio.

http://tgrc.ucdavis.edu/Data/Acc/AccDetail.aspx?AccessionNum=LA2175&contains=false



This was on tater mater proboards a quote from Darrel Jones. LA 2175 may be of interest for both this and obligate outcrossing tomatoes. If not already included.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Dominic J on 2020-02-17, 06:13:48 AM
And if taking eyes off LB for a moment, some of these also have interesting resistances to other diseases. Mountain Magic, for example: "High resistance to Fusarium wilt races 1, 2, and 3, late blight, and Verticillium wilt; and intermediate resistance to early blight."

When I first started growing tomatoes, I basically looked at the resistance codes, and picked the one with the most of them, and that brought me to Mountain Magic (along with a few others). I never had any disease problems with Mountain Magic, and it's been a staple of my garden ever since. Also the kids actually eat it.

It's unfortunately not homozygous for Ph2 and Ph3, but it's got them and still worthy of consideration for inclusion, I think.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: triffid on 2020-04-25, 12:57:10 PM
I've read in Deppe's book that Geranium Kiss outlived all others in rainy blight season, but the particular genes that allow for this are unknown. Has anyone else found it resistant in their garden? I'll be trialing it on the plot this year.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Diane Whitehead on 2020-04-25, 01:38:47 PM
It hasn't had blight for me, but then, it is an early determinate so it wouldn't get it.

 We only get late blight when it rains, which happens in September.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Garrett Schantz on 2020-09-13, 04:01:31 PM
Galahad doesn't have early blight resistance but Johnny's seeds lists "exceptional" late blight resistance. "High resistance to Fusarium wilt (races 1, 2, and 3), gray leaf spot, late blight, nematodes, tomato spotted wilt virus, and Verticillium wilt." Also apparently has a decent taste according to Johnny's and some blogs. Don't really see too many tomatoes with all of these different high resistances. Figured I would mention it here.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Diane Whitehead on 2020-09-13, 08:11:09 PM
Good heavens!  If I gardened in an area with all those diseases, I would just buy tinned tomatoes.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: reed on 2020-09-14, 01:42:03 AM
I think every tomato disease know is ubiquitous where I live but I still grow plenty of tomatoes.  Sometimes they do croak completely in late season but our canning jars are already full by then so I don't care all that  that much.
 
I have never done much of anything except save seed if I have choice, from less infected plants. And I compost old vines in the spot they grew and put tomatoes in a different spot the next year. Plenty of diseased leaves drop off anyway and the diseases are everywhere anyway so there is no point in wasting organic material in the interest of garden cleanliness.

I have recently been de-hybridizing the varieties Iron Lady and Celebrity. I grow the decedents of these in close proximity to my favorite Mr. Stripey (not Tigerella) in hopes a cross might happen. The F1 of Iron Lady was terrible flavor wise but some offspring after two seasons are much better.

Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Diane Whitehead on 2020-09-14, 09:48:18 AM
I am also de-hybridizing various blight-resistant ones -Iron Lady, Ferline. Losetto, Crimson Crush, Cocktail Crush.

A fawn managed to squeeze itself into my deer-proof area and eat the tops off them all.  I still haven't found the place where she is getting in but I will dig up what remains of the plants and plant them in my greenhouse, hoping for tomatoes from them in the winter.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2020-11-30, 03:11:35 PM
In 2021 i will start with some F2 plants from Galahad. Galahad is a F1 homozygous ph2 and ph3 beef tomato. Do u guys know the pedigree of Galahad?
Is it a cross from beef, normal or cherry tomato parents?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2020-11-30, 05:48:14 PM
I am most excited about the dehybridizing Lizzano so far. Short season enough to be good breeding material. Iron lady and Skykomish are a bit long season here. Though no blight here for the most part, hit about ten or fifteen years ago. So it will be back sometime.

Edit: I don't know if my Lizzano was Lizzano for certain. I would need to get more Lizzano to check.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2020-12-01, 01:13:05 PM
I think Mountain Magic is a good F1 to dehybridizing because one parent is a good producing beef tomato with ph2 and ph3 and some other disease resistant genes. The other parrent is a very sweet orange cherry tomato with the Rin gene. Dehybridizing can give a very good cherry tomato with good flavor, Rin gene for long hangtime and resistance for blight ph2 and ph3.

Some other selections from Mountain Magic can give very good beef tomato`s.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-04-12, 02:36:31 PM
I don't think exsertion is much of a hedge against unintended PH2 and PH3 loss, inbreeding is inbreeding regardless of some percentage of uncontrolled crossing and if I select for the external traits I want; essentially reselecting for Big Hill, I stand to loose the PH2 and PH3 traits which I can't see. I think the best course of action is to save and perhaps freeze F1 and F2 seed and or send it to someone who regularly has bad late blight now. Though another route might be to maintain a large population size while minimizing selection.

I wonder how much it would cost to do marker assisted selection for PH2 and PH3 in terms of doing this Deppe style Iron Lady PH2 and PH3 introgression. I wrote one such company and asked. Will see if they respond.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Joseph Lofthouse on 2021-04-12, 04:49:34 PM
Following the example of Raoul Robinson in Return To Resistance, would lead us to eliminate all known resistance genes from the population. And then select among the inter-crossing survivors for whatever can eek out an existence. This selects against a few alleles with large effect -- that are subject to short-term defeat, and selects for a multitude of alleles with minor effects -- which add up to robust long-term resistance.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-04-12, 06:47:30 PM

As for the reference to Raul Robinson--this refers to the idea that there is "horizontal" and "vertical" resistance, that these are actually different from each other, and that "horizontal" is slower to be overcome by the evolution of the pathogen. It's additionally assumed that horizontal resistance is dependent upon multiple genes with small affects, and vertical resistance is dependent upon one gene with major effects (the sort of gene university breeders transfer into their varieties). It's normally assumed that heirlooms have horizontal resistance, but this is only until someone actually does some crosses and looks.

Then, my impression is that the heirloom usually turns out to have no measurable resistance--or it actually has one of those major resistance genes, exactly the same ones involved in "vertical" resistance. Ph1 is a good case in point. It was present in a number of heirlooms, which would undoubtedly, in the absence of serious genetic investigation, been called "horizontal" resistance. It conferred serious resistance in its day. However, it was overridden by more modern lines of late blight, and now doesn't confer useful resistance.

Whether a variety's resistance is easily out-evolved by the pathogen is not any such simple thing as one-gene-bad, more-genes good, either. For example, Jim Baggett's pea varieties that carry one gene for resistance to pea enation virus and one for powdery mildew and one for wilt--which let's them be grown all the way from spring to fall--are still nicely resistant to the respective diseases, though they have been around for decades.

Generally, though, from first principles you can guess that if you have two different major genes for resistance to something, your variety is less vulnerable to evolution of the pathogen than just one.

Ph2 and Ph3 show a different repertoire of what lines of late blight they are sensitive too. However, both genes act as codominants and act quantitatively with respect to each other. So varieties that are homozygous for both generally show strong resistance to all strains of blight; varieties that are homozygous for just one, or heterozygous for both show less resistance, with levels more dependent upon specific strains.

Another way of looking at it. Let's suppose that after we've developed a new generation of heirlooms with Ph2 and Ph3 in them, whether someone who didn't know what we did would call them "horizontal" or "vertical" resistance. Well, before they did serious genetics, they would probably just assume they had horizontal resistance. If they then went and did the serious genetic analysis in the absence of testing specifically for Ph2 and Ph3, they would probably still think the resistance was horizontal. Because it would look quantitative under field conditions.

One thing that is very valuable about working with wild material is you might discover additional genes conferring serious resistance to late blight. To show up as a QTL in something as hard to evaluate as disease resistance, especially in variable material, you pretty much would be talking about genes with major effects, by the way. Various university breeders are still "mining" wild material looking for new genes. Additional new genes would be valuable. Could you test for them using marker assisted selection? No. Marker assisted selection is based upon someone having identified a distinctive DNA sequence in or near the gene for resistance. So you could test wild-derived late-blight resistant material to see if it contains Ph2 or Ph3. But not PhX, something new. Of course, if your material doesn't have either of those genes and is resistant, it presumably is something new. So then you'd just give some to one of the university groups which is spending day and night looking for new Ph genes, and they would undoubtedly be very happy to do the molecular biology and identify a marker for the gene.

Carol had this reply to a prior discussion of this. My response is simply to try both approaches. Belt and suspenders.

Garden space wise Carol's approach will probably never use more than space for a couple tomato plants in my garden. Couple Iron Lady's maybe a couple F1's to grow some F2 seed. Unless I get hit by blight and then it might expand. One packet of ten Iron Lady seeds is down by four seeds after three years. Also I do expect that if late blight does hit and stay sometime I'll still be able to grow tomatoes inside and in the greenhouse and work on this after the fact.

The general diversity approach implicit in the obligate outcrossing approach of Joseph's and the similar exserted stigma Kapuler approach tomatoes well those already have most of my garden. In theory if blight hits maybe a few of those hyper diverse interspecies hybrid resulting tomatoes will be resistant and get seed saved.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-10-02, 07:40:11 AM
This is in the other post as well

I found the list:
Homozygous for Ph2 and Ph3
Iron Lady
Lizzano
Skykomish (from Tom Wagner)
Crimson Crush

Skykomish seems to be homozygous fpr ph2 but has no ph3 genes.

Do u have some source about the homozygous genes from Crimson Crush F1?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-10-02, 09:07:24 AM
It seems to me that Iron Lady F1 as recommended by Carol Deppe in her book may be our safe bet. My plant had a tiny bit of modest exsertion of the stigma this year which was unexpected. I saved a couple hundred seeds for an F2 this time but did not manage a cross.

It strikes me that a good way to proceed with Carol's schema of systematic late blight protection for heirloom style tomatoes would be to utilize the 100 plus existing OSSI tomato lines. Cross each of those to Iron Lady and release the F2s to growers in late blight prone areas. The resulting F2s would already have OSSI protection from the OSSI parent.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-10-02, 11:05:28 AM
Think its better to use Galahad F1 for crossing with heirloom.
Galahad F1 is homozygous for ph2 and ph3. And have much better tast as Iron Lady F1. Galahad F1 have Brandywine in the perdrigree.

Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-10-02, 03:31:19 PM
Interesting Galahad F1 is available from Johnnies. Shorter season is a big plus.

https://www.johnnyseeds.com/vegetables/tomatoes/beefsteak-tomatoes/galahad-organic-f1-tomato-seed-4055G.html
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2021-10-03, 01:06:35 AM
I have not be able to find any data about Galahag and homozygous ph2 & ph3. Any source ?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-10-03, 05:04:44 AM
My source for homozygous ph2 and ph3 gene in Galahad F1 is Dr. Jason Robert Cavatorta himself.
Also my 51 F2 Galahad plants show the same blight resistance as the F1. And this year the supposed resistant varieties got strong blight infection:
Rote Murmel
Koralik
Dorada
Primavera
Clou
Red Pearl
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2021-10-03, 06:02:54 AM
Nice ! Galahad making into my buying list right now :)
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Steph S on 2021-10-03, 06:17:25 AM
Yeah!  I read the description at Johnnies - sounds like Galahad would make a good standard to compare disease resistance with my home bred varieties, even though LB has not been the issue here, because it has such a spectrum of resistances. 
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Garrett Schantz on 2021-10-03, 09:37:42 AM
Crossing Iron Lady F1 with Galahad F1 could be an option if someone really wanted Early Blight resistance.

I sometimes get early blight, almost always end up with late blight by the end of the season.

Should be easy enough to select for most of the blight resistant traits. I would have to send the offspring out to people who have problems with Septoria, Nematodes, Grey leaf spot, Spotted Wilt and fusarium wilt to test for the other resistances.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-10-03, 03:00:10 PM
After growing it again this year I am certain that what I've been growing as dehybridizing Lizzano is actually a stable early red micro dwarf and I've no idea if it has any relation to real Lizzano F1. It was quite similar to "pinnochio" micro dwarf which I also grew.  Would need to grow out some real lizzano F1 a few generations to know I guess. Not sure but I think we decided that Lizzano F1 does NOT have both PH2 and PH3 homozygous? Which might be the end of my Lizzano experiments.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Arjan vD on 2021-12-01, 10:41:18 AM
This year our weather was really bad, spring was very cold and summer was very wet and because of that almost all my tomatoes were infected with late blight, so this was a good year to evaluate which varieties have some real resistance against late blight.

The ones that dit well were Galahad, Damsel, matt's wild cherry, solanum pimp.LA1269 and from the Joseph Lofthouse strains I had one of the Wildlings with real good resistance. The other wildlings were all heavily affected with late blight.
The ones that did poorly were
Skykomish, Big Hill, Sasha's altai, Oaxacan Jewel, Buffalo sun, Q-series, Bh- series, most of the wildings except one, pimp.LA0417, Piennolo X LA0417, Sungold F1,North Queen and Primabella

I also grew a F2 of a cross of Weight in Gold and Dwarf Champion Improved outside and it wasn't late blight resistant but one of the plants had a much better tolerance so I kept seed of that one.

I hope this information will be helpfull

Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-01, 12:40:03 PM
Galahad is very good, how is the taste in comparison with his half brother Damsel?

Strange you are Primabella was disappointing?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2021-12-01, 01:24:05 PM
Interesting, Skykomish and primabella are supposed to have some LB resistance.

We get a pretty bad year too (France), and wildings and Q-series all have succumbed to LB. Only Iron Lady F1 and some plants from BH had some resistance.

Have you been able to taste the resistant wildling ?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Adrian on 2021-12-01, 01:32:37 PM
 The french climate is extremly variable one year on other.
We can have a extrem dry and hot year as a extrem humid year.
I have try cross between potato leaf x wispy leaf tomato this year for have a great resistance at the rain period followed of the heatwave.
The better for me was canestrino di lucca.It was very surprising and i don't know these  genes resistance against the blight.I doubt she has ph2 but it the most resistant!

I think the heterosis effect can play on the blight resistance and others diseases.A promiscious tomato is for me a good solution.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-01, 02:29:17 PM
It seems Skykomish have only ph2 genes and no ph3 genes.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-01, 07:22:14 PM
Galahad F1 sounds nice but I don't want it terribly since I already have so much Iron Lady F2 seed saved from last summer.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Garrett Schantz on 2021-12-01, 07:43:41 PM
Almost none of Joseph's wild series did that well for me either. I'm going to end up selecting for blight resistance heavily, next year. I'm assuming that there's some good traits present in there somewhere.

Planning on crossing Wild Gem with exserted orange or something similar, as all my Wild Gem plants were heavily resistant to whatever type of blight that I had this year. Wild Gem was slightly exserted - hoping that this aids in selection for exsertion. After that, I can cross the resistant Wild series types and continuously select out what performs the best for me.

Pretty much all of my habrochaites except for Joseph's landrace handled the blight well enough.

Probably the case that Joseph doesn't have selection pressures for blight. I should be able to help out a bit with that.

Might play around with Galahad as well.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-01, 08:42:30 PM
Wild Gem sounds fun. Wild Gem x Exserted Orange sounds like a great plan.

I think it is definitely the case that Joseph much like myself has little access to blight. Personally my main hope for blight breeding is to mail off F2s to someone like you who actually has a shot at testing them.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Arjan vD on 2021-12-02, 04:44:26 AM
What might be interesting is that the wildling with good late blight resistance had a bit different leaf than the other plants. It was a large sprawling indeterminate vine and it had a bit less hair on the leaves than the other wildlings.
Flowers were a bit on the small side and were not promiscuous. Fruit was about 3 tot 5cm in diameter and orange yellow bicolor.

Could it be that it has some pimpinellifolium in its genetics? Unfortunately I don't have a picture of the plant.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-02, 05:42:27 AM
What might be interesting is that the wildling with good late blight resistance had a bit different leaf than the other plants. It was a large sprawling indeterminate vine and it had a bit less hair on the leaves than the other wildlings.
Flowers were a bit on the small side and were not promiscuous. Fruit was about 3 tot 5cm in diameter and orange yellow bicolor.

Could it be that it has some pimpinellifolium in its genetics? Unfortunately I don't have a picture of the plant.
I bet they about all have some pimpinellifolium if as we suspect the early reds like Jagodka, NoID, and Brad have some introgression. Hillbilly sounds like a true heirloom. From the penellii side there was some sort of standard reds used. Though Andrew was quite keen to add the second penellii rootstock because the red used contributed an important resistance gene. All of which track to specific introgressions  most of which when I Googled track back to pimpinillifolium. I'm not sure that second penellii rootstock is yet in the most advanced populations though. I have plenty of seed still though. Though I suspect the first was probably similar.

Edit: cv. VF36 is the domestic on what I think was the first penellii. Probably a boring lab red though I failed to find details on quickly. The second penellii line was NC84173 which is a little confusing because it tracks to both a red parent line and some sources list it as the original line name for "Mountain Gold" which cannot be true without an additional cross as the red is determinate and the yellow indeterminate. Though a little irrelevant because the latter to my knowledge has not yet made it to elite status in the project.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-02, 12:13:39 PM
Galahad F1 sounds nice but I don't want it terribly since I already have so much Iron Lady F2 seed saved from last summer.

Why will u go on with Iron Lady F2?
there are much better and also homozygous for ph2 and ph3:
Galahad, very good taste
Mountaineer Pride (child of Iron Lady), not a good taste

I understooth Iron Lady is very bad tasting.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-02, 12:54:25 PM
Why will u go on with Iron Lady F2?
there are much better and also homozygous for ph2 and ph3:
Galahad, very good taste
Mountaineer Pride (child of Iron Lady), not a good taste

I understooth Iron Lady is very bad tasting.

I do a lot of thinking out loud! Now that you have asked my realization is that I am being extraordinarily cheap. It looks like a packet of Galahad F1 organic from Johnny's would cost me $12.15 usd including shipping.

I'll probably end up getting a packet as that isn't a good reason.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Diane Whitehead on 2021-12-02, 02:25:53 PM
only one packet?  Johnny's will pay the postage if you buy $200 worth.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-02, 02:51:11 PM
only one packet?  Johnny's will pay the postage if you buy $200 worth.

I only ever want about one packet of anything!

Except for that one time from Joseph!
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-02, 08:17:10 PM
It's a little cheaper from Territorial for ten seeds but the shipping makes it $13.10 usd. Wonder if I can find it on a seed rack anywhere.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-20, 09:33:01 AM
Found this AAS winner called purple zebra f1. It has ph2 and ph3 but no idea if homozygous. Still potentially useful when trying to isolate a trait like striping. Grown as a dehybridization some segregates would almost certainly become homozygous for both in an area with heavy late blight pressure and the striping should be stable as it seems to be recessive at least in my limited experience.

Also found on the territorial website Buffalosun F1 a bicolor and a few other new hybrids including Darkstar which list LB but not if they are PH2 PH3 homozygous. They are also out of stock on smaller packet sizes. Still more colors of tomato with some late blight resistance increases the variety of late blight resistant tomatoes a late blight afflicted grower/breeder might have to work with.

With a collection of say Darkstar F1, Buffalosun F1, Galahad F1, Purple Zebra F1, Lizzano F1, and Iron Lady F1 you would certainly have the beginnings of a nice colorful and variable late blight resistant grex.

It might be worth crossing hybrids with homozygous PH2 and PH3 like Iron Lady F1 to open pollinated varieties with some late blight resistance to get higher levels of resistance faster. Would be especially true for someone working in an area currently prone to late blight or if the worst-case scenario Carol predicted came to pass and the spore producing strains became endemic everywhere in the U.S. Which would turn my area into being oh say a once in 20-year Late blight problem to a every year late blight problem as soon as it got here.

In terms of days to maturity which is an important consideration for me these are all over the place Lizzano F1, Galahad F1, and Purple Zebra F1 are all reasonable as transplants here.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-20, 01:39:44 PM
The wet year in 2021 show the recistance of Buffalosun F1 is not based on ph2 and ph3. It was very susceptible for phytophthora.

Purple zebra F1 is heterozygous for both ph2 and ph3. Hope someone can ship seeds for 2022 to Netherlands?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-20, 03:13:58 PM
Speaking of different sources of LB resistance ph4 is available but seldom mentioned. I recently obtained a ph4 accession though I'm not sure what the utility is? Then ph5 is supposed to be good and Carol said she expected Oregon State to release it shortly a few years ago and we seem to still be waiting.

Buffalo Sun F1 seems about the same as Skykomish as far as utility for late blight breeding. Very long season bicolors with partial resistance.

In the Netherlands do you have the spores that overwinter Roland?

Would it work there to grow the heterozygous purple zebra f1?

Does EFN ship there?

I've been wondering if it might be possible to put together an interesting segregating grex of crosses with LB resistant varieties and offer it through EFN.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Garrett Schantz on 2021-12-20, 09:40:25 PM
Purple Zebra F1 is sold by A.P. Whaley as well.

Some other Frogsleap Farm tomato varieties are sold there as well.

Appears to ship internationally.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Tim DH on 2021-12-21, 05:41:05 AM
A new ''Late Blight Resistant'' variety, showing up in England for the first time, but loads of sellers carrying it, is Primabella. I didn't stumble upon it last time I searched. About 6 months ago. ... So I'm guessing some mega seed supplier has done a massive grow-out.

It's open pollinated. One website mentions sister varieties from a German breeding program.

Tim DH
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2021-12-21, 06:36:00 AM
Its from Culinaris : https://culinaris-saatgut.de/?s=Toleranz
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2021-12-21, 09:21:48 AM
Does EFN ship there?

I've been wondering if it might be possible to put together an interesting segregating grex of crosses with LB resistant varieties and offer it through EFN.

Yes EFN ships to Europe. That would be a very good use of EFN to spread seeds to other places.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-21, 12:29:39 PM
Speaking of different sources of LB resistance ph4 is available but seldom mentioned. I recently obtained a ph4 accession though I'm not sure what the utility is? Then ph5 is supposed to be good and Carol said she expected Oregon State to release it shortly a few years ago and we seem to still be waiting.

Buffalo Sun F1 seems about the same as Skykomish as far as utility for late blight breeding. Very long season bicolors with partial resistance.

In the Netherlands do you have the spores that overwinter Roland?

Would it work there to grow the heterozygous purple zebra f1?

Does EFN ship there?

I've been wondering if it might be possible to put together an interesting segregating grex of crosses with LB resistant varieties and offer it through EFN.

Its not clear for me if we have spores that overwinter. Most people say the phytophthora start in potatoes and later it get to tomatoes.

In Netherlands is working:
Homozygous ph2 is not working
Heterozygous ph3 is giving a bit resistance but not enough
Homozygous ph3 is working very well
Heterozygous ph2 and ph3 is working very well
Homozygous ph2 and ph3 are best but there is still some infection.

Hence Purple zebra F1 heterozygous for ph2 and ph3 have very good potential for Netherlands.

ps Skykomish seems to be homozygous for ph2 and do not show resistance in Netherlands.
The cross of Skykomish x Primabella  is working very well because this cross is heterozygous for ph2 and ph3.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-21, 12:32:32 PM
A new ''Late Blight Resistant'' variety, showing up in England for the first time, but loads of sellers carrying it, is Primabella. I didn't stumble upon it last time I searched. About 6 months ago. ... So I'm guessing some mega seed supplier has done a massive grow-out.

It's open pollinated. One website mentions sister varieties from a German breeding program.

Tim DH

I grow Primabella for serveral years. Resistance is very good.
Primabella is a inbredline of Philovita F1. Philovita F1 is heterozygous for ph3. Hence Primabella seems to be homozygous for ph3.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Tim DH on 2021-12-22, 03:55:04 AM
Hi Roland,
   Thanks. ... That is useful/helpful information.

Tim DH
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Tim DH on 2021-12-26, 02:31:16 PM
Hi Roland,
   You state that 'Homozygous ph2 and ph3' are best. ... Can you name any varieties?
   I assume your interest in Zebra F1 is because growing it out should produce some 'Homozygous ph2 and ph3'?
   Are you also growing out 'Skykomish x Primabella' with the same aim??

Tim DH
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-26, 03:29:50 PM
I'm still not convinced that anything available here in the U.S. but Iron Lady is homozygous PH2 and PH3. Sounds like Galahad is homozygous PH3.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-27, 06:35:01 AM
There are not many homozygous ph2 and ph3 tomatoes:
Galahad F1 ph2 and ph3 homozygous
Mountaineer Pride OP ph2 and ph3 homozygous
Iron Lady F1 ph2 and ph3 homozygous

Purple Zebra F1 ph2 and ph3 heterozygous
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-27, 09:09:25 AM
https://eorganic.org/node/10822 clear reference for Carol Deppe's published PH2 PH3 homozygous assertion for Iron Lady F1.

Galahad F1 is very new so there isn't much information. However found an announcement by the breeder recently on facebook. It asserted PH3 homozygosity not both. That is not necessarily bad though PH3 homozygosity may be very useful. https://m.facebook.com/groups/479332809623391/permalink/522096665347005/?m_entstream_source=group

Mountaineer Pride was released in 2017. https://wvliving.com/a-better-tomato/amp/
Can't find a ph2 and ph3 reference. This linked article does confirm Iron Lady in the back ground in their search for septoria resistance so it is possible but I would like to see it in a reference.

Have been down this path before and I need a reference to believe.

With the purple zebra the heterozygous condition suggests that in the subsequent generations you might be able to simply stabilize it and it must get stripes from both parents. Which means a lot of the work towards a striped open pollinated late blight resistant has already been done.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Tim DH on 2021-12-27, 01:44:16 PM
Trawling through old Tomatoville posts. I discover that back in 2010 Tom Wagner thought Skykomish was homozygous for ph2 & ph3.

He also mentioned a variety called ‘Make My Day’ which is also homozygous ph2 & ph3.
The post is dated 14th Sept 2010, but I can’t find any more recent references to this variety. Curious.

Apart from that there is another AAS variety which mentions blight resistance, Jasper F1. My interest in this is that it is listed as 60 days (Purple Zebra F1 is 80/85 days) Does anyone happen to know what sort of blight resistance Jasper has?

Tim DH
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: nathanp on 2021-12-27, 02:16:54 PM
Trawling through old Tomatoville posts. I discover that back in 2010 Tom Wagner thought Skykomish was homozygous for ph2 & ph3.

He also mentioned a variety called ‘Make My Day’ which is also homozygous ph2 & ph3.
The post is dated 14th Sept 2010, but I can’t find any more recent references to this variety. Curious.

Apart from that there is another AAS variety which mentions blight resistance, Jasper F1. My interest in this is that it is listed as 60 days (Purple Zebra F1 is 80/85 days) Does anyone happen to know what sort of blight resistance Jasper has?

Tim DH

See this topic for link to an article that tested Skykomish.  Skykomish as tested is heterozygous for Ph2 and lacks Ph3.  But it was listed amount the most resistant tomatoes in the 2011 trial.  Make My Day also tested similarly.  I would guess they have some other resistance that has not yet been quantified.  Matt's Wild Cherry is similar with acknowledged resistance, but not Ph2 or Ph3.

http://opensourceplantbreeding.org/forum/index.php?topic=58.75 (http://opensourceplantbreeding.org/forum/index.php?topic=58.75)

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjh96--vrDtAhVfFVkFHRUmBzUQFjAFegQIBxAC&url=https%3A%2F%2Fresearch.bangor.ac.uk%2Fportal%2Ffiles%2F20580359%2Fnull&usg=AOvVaw1Z33V1p5OPTTn63oQLYgHIaaa (https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjh96--vrDtAhVfFVkFHRUmBzUQFjAFegQIBxAC&url=https%3A%2F%2Fresearch.bangor.ac.uk%2Fportal%2Ffiles%2F20580359%2Fnull&usg=AOvVaw1Z33V1p5OPTTn63oQLYgHIaaa)

I should mention that there are four other tomatoes that tested homozygous for both Ph2 and Ph3
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-27, 02:24:42 PM
I think we have ruled out good resistance in Skykomish. It worked in Washington state for Tom but hasn't been widely useful elsewhere and reports from our fellow board members suggest it isn't so. I think I looked and tried but could not locate Make My Day, it may still be in someone's collection so try asking around. No reason to be absolutely certain it is if Skykomish isn't. Tom has written about having a large number of introgression lines ready to be tested against late blight on the shelf, but he has hopes of making some money from some of his extensive work so isn't releasing some of what he considers to be his best stuff. I hope it works out somehow, but I am concerned it may just be really hard to make money at this sort of tomato breeding!

That same eorganic article https://eorganic.org/node/10822 references Jasper F1 but not Lizzano F1. Jasper has very good resistance to the US-23 strain of late blight and the source of that is unknown- Edit from Nathan's link above it is heterozygous for PH3. Lizzano F1 at 63 days may only have PH2 according to the article Nathan just linked. We thought for a time it was homozygous for both on this forum. I would suggest Lizzano F1 as well as Jasper F1 for a short season possibility as 60 vs 63 days is not really much difference. Though Lizzano is a basket type. I got some F2 Lizzano seed but I am not certain it was Lizzano as what I ended up with was a microdwarf and grown near Pinnochio microdwarf this summer I couldn't really see any difference between the two. I kind of want to get new Lizzano seed and see if it segregates out microdwarfs. I actually got a packet from Amazon last year and I suspect it was a fraud as the seeds don't look like tomato seeds and did not germinate. So a packet from a reputable source and see if it does indeed so segregate in the F2!

Sounds to me like most late blight resistant varieties might be best used as a parent to cross to Iron Lady F1. Which would mean an Iron Lady F1 x Lizzano F1 or alternatively x Jasper F1 would be a good route to go to try to find segregants that are short season and highly resistant to late blight. Same with Purple Zebra- Iron Lady x Purple Zebra would give you a higher chance of getting a homozygous PH2/PH3 striped tomato in the F2 segregants though the F1 would not be striped if my experienced with Exserted Tiger is any indication. If Late Blight becomes a huge problem in short season gardens or already is that doesn't leave many short season let alone colorful options.

Personally, I still think it would be most interesting to cross Iron Lady with my own varieties to try to spread those exserted stigma genetics to places where they otherwise wouldn't be able to grow because of Late Blight pressure.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-27, 05:35:17 PM
Table 2.6 and 2.7 in that PhD thesis do list some more varieties as PH2/PH2 and PH3/PH3 however when I searched the document for "Table 2.6" I found an explanation that both Table 2.6 and Table 2.7 should be utilized with caution because the testing method was a little hard to interpret for a couple reasons so might have thrown some false positives.

Table 2.6 lists Ailsa Craig but Table 2.7 lists Ailsa Craig as not resistant. The others are Amai, Bella Rosa, and Matina in Table 2.6. None of which appear to be known for blight resistance when I searched for seed sources.

Now Table 2.7 lists quite a few more including Iron Lady F1 but everything but Iron Lady F1 seems to be a breeding line number shared with the researcher. Meaning that we have just Iron Lady F1 to work with.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Tim DH on 2021-12-28, 01:57:40 PM
Hi Nathanp
   Thanks for re-posting the link to that article. …. Only 214 pages long, so its taking a little while to digest!
   It does mention BOTH varieties I was asking about. (Jasper is heterozygous ph3)

   Interestingly the PhD was part of the development program for ‘Crimson Crush F1’ which no one on here is talking about. It would be reasonable to assume that CC is one of the three experimental varieties which showed promise. It pretty much says so on page 13.

   Incidentally the article also mentions grafting conferring Blight resistance, irrespective of whether the rootstock has Blight resistance!! (p29)

   I’ve been thinking further about William’s concerns regarding breeders being able to turn a profit. On one level it wouldn’t make sense for a commercial outfit to release a homozygous ph2&ph3 because we’d treat it like an open pollinated variety! We wouldn’t have to go back every year for fresh seed.

   SO there possibly is merit in trying to grow out F1 heterozygous ph2&ph3s, because in the homozygous state we might end up with a better variety.

   I wonder if CC is an F1, but homozygous for ph2&ph3! My reading of the article would suggest it is!! Possibly its just ‘called’ an F1 to dissuade seed saving? ((Now I’m wondering what the actual status of Purple Zebra is.))

   Lastly (for now) This article was inconclusive about the nature of Blight resistance in Koralik. I’ve come across a later paper from the same stables suggesting that Koralik has a differently mediated Blight resistance.

https://research.bangor.ac.uk/portal/en/researchoutputs/qtl-mapping-in-salad-tomatoes(db230825-92e0-4c75-892b-b295f0201c7c).html

   Some seed sellers call Koralik a heritage variety, some call it an F1. To add to the confusion some list it as ultra early and some list it as late! Perhaps there are two Koraliks??

Tim DH
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-28, 03:06:31 PM
Some fraction of the F2 and subsequent generations of the heterozygous F1s should turn up homozygous for PH2 and PH3.

In Galahad F1's breeder Jason Cavatorta's Facebook post about Galahad F1 he said something about a linked resistance on the same chromosome on PH3 that was hard to recombine because he wanted both resistances. That sort of difficult breeding might be harder than the PH2 and PH3 breeding for late blight  that Carol Deppe proposed.

I think the professional breeders know that a small fraction of us will dehybridize any F1 they release to us. Particularly relatively independent small breeders probably have little interest in making it impossible for us to do that effectively.

However, there might still be some hybrid situations we cannot easily replicate.

We could make some open source hybrids though with open source recipes.

One way to start that could be to desegregate name and ossi pledge a descendant of Iron Lady F1 so we have a named replicable PH2/PH3 homozygous parent line. Then keep a running list of good open source combinations. One way to do that might be to  test cross it with every registered OSSI tomato. Just throwing that out there since it represents a lot of work...
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Diane Whitehead on 2021-12-28, 03:30:44 PM
Is there an easy way to test for resistance to late blight, or do we just have to grow out a lot of plants and wait for some spores to blow into the neighbourhood so we can see which ones remain healthy?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: nathanp on 2021-12-28, 04:23:29 PM
do we just have to grow out a lot of plants and wait for some spores to blow into the neighbourhood so we can see which ones remain healthy?

This is why I got precisely nowhere with anything I have done with LB lines.  No noticeable LB has shown up since about 2013 or 2014.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-28, 04:29:17 PM
Is there an easy way to test for resistance to late blight, or do we just have to grow out a lot of plants and wait for some spores to blow into the neighborhood so we can see which ones remain healthy?

Depends on your funding! Marker assisted selection is available. Jason Cavatorta posted this recently: https://www.facebook.com/groups/479332809623391/posts/911998313023503 to the "Tomato Breeders" group on Facebook.

There I asked him a question about how he does it and he uses agbiotech in California. https://agbiotech.net/dna-markers/?fbclid=IwAR2tgIaL-QuhNzxn_q2z_IaLTJYB9gFrzlZLK4TzlbhITOVUXxxQ2XydEDA you can click on the tomatoes there and see that they offer PH2 and PH3 testing a long with a lot of other tomato genes.

They can just test for PH2 and PH3 for us. Which probably wouldn't be too expensive for one set of tests. It would be pretty expensive though for a whole segregating F2 I am guessing.

I'm a little afraid to email them and ask what it costs because so far, my tomato varieties are worth about $50 a year if I grow them out myself and sell the seed which I have decided not to do for 2022. (I just sent them a question about the cost of the testing).

So let's say I wanted to make Exserted Orange into a PH2 PH3 homozygous line. I would cross it to Iron Lady and get a PH2 PH3 Heterozygous F1 every time. Then I could grow out the F2 and have every plant tested for PH2 and PH3. Any that tested as homozygous (if that is possible) could then be continued with.

Alternatively, we rely on those group members who have bad and fairly regular late blight to narrow things down a bit. If we had a really good performing say F6 we could just test it. Or just rely on its performance.

Another strategy to minimize testing costs might be to cut down on the likelihood to need as many repeat tests by back crossing to Iron Lady or by making an initial cross to a variety that would cut down on the chances of the offspring not being homozygous. For instance, if we wanted to cross Iron Lady F1 which is PH2/PH2 and PH3/PH3 with Galahad F1 which we know is at least PH3/PH3 we would only need to test the offspring for PH2 which means half the testing. Or if we wanted to cross Purple Zebra F1 which we currently think is heterozygous for both PH2 and PH3 with Iron Lady F1 it would be like backcrossing once to Iron Lady F1. Significantly more likely to have homozygous outcomes and should cut down the number of generations you would need to test.

Could also just do a lot of stabilizing and back crossing to Iron Lady F1 until you got a plant that was very likely to prove homozygous PH2 and PH3 before testing- basically introgression of whatever important traits you wanted into Iron Lady. 

My thought to avoid testing costs is to just never personally create a finished variety for Late Blight Resistance but instead make crosses and then freeze some F2 seed and send some off to collaborators.

I started a thread for this, but I am curious basically about how much variation there is in Iron Lady. There has to be some to get hybrid vigor. It is possible that we could dehybridize multiple lines from Iron Lady for different trait variations. Like how short season could we get a dehybridized Iron Lady if we selected strongly for that desired outcome? I suspect the answer lies mostly in how much difference there is in days to maturity on the two breeding lines they use to make Iron Lady each year. Same with fruit size. I would expect both parents to be boring red tomatoes so it would be relatively minor differences. 
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-28, 11:04:45 PM
https://territorialseed.com/collections/new-products/products/purple-zebra

Territorial's description for Purple Zebra F1 is very good sounding. Much closer to Carol Deppe's vision of creating heirloom quality late blight resistant tomatoes than Iron Lady. If it were possible to desegregate Purple Zebra F1 into a homozygous PH2 and PH3 line it would be far better than Iron Lady F1. As a desegregation project it strikes me that the color and striping should be stable- that they must have used two purple striped parent lines to produce Purple Zebra F1.

I was looking at Carol's old posts on here and she actually suggested backcrossing to the heirloom not Iron Lady F1. She thought it would be hard to get rid of the Iron Lady F1 flavor. So particularly for that first improved variety the introgression of PH2 and PH3 into an heirloom quality tomato would be hard.

So it looks like Mark Mccaslin and Frogsleap Farms have created a very interesting tomato with this one. Essentially accomplishing that first step of getting PH2 and PH3 into a tasty tomato. Which means desegregating it maybe should be a priority.

https://all-americaselections.org/product/tomato-purple-zebra/
https://frogsleapfarm.blogspot.com/?fbclid=IwAR3OhNctblhUNV0LulZr9_RvJkhV-PmUQOGsBph5Lkq0qUWNbgXXiO74oMs

Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-28, 11:24:59 PM
Its not clear for me if we have spores that overwinter. Most people say the phytophthora start in potatoes and later it get to tomatoes.

In Netherlands is working:
Homozygous ph2 is not working
Heterozygous ph3 is giving a bit resistance but not enough
Homozygous ph3 is working very well
Heterozygous ph2 and ph3 is working very well
Homozygous ph2 and ph3 are best but there is still some infection.

Hence Purple zebra F1 heterozygous for ph2 and ph3 have very good potential for Netherlands.

ps Skykomish seems to be homozygous for ph2 and do not show resistance in Netherlands.
The cross of Skykomish x Primabella  is working very well because this cross is heterozygous for ph2 and ph3.

Seems like Skykomish x Galahad F1 would work well also. I don't think we can get Primabella easily in the United States.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2021-12-29, 05:49:28 AM
Do u guys know the late blight genes from tomato Darkstar F1?

https://territorialseed.com/collections/tomato/products/darkstar?variant=41647595880622
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2021-12-30, 01:03:25 AM
I tried searching for dark star. Didn't find anything notable. Funny how some breeders seem to give out more info than others. Though we may be in a small minority who get really excited to see details on exactly what kind of late blight resistance a variety has.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-03, 01:28:11 PM
I got a bonus packet of Geranium Kiss in a seed order today from J & L gardens. Last night I was rereading Carol's book and it is one she mentioned as being bred by Alan Kapuler and believed to have unknown late blight resistance supposedly form Lycopersicon humboldtii a taxon that has been lumped back into probably domestic tomatoes would be my guess. 60 DTM and pointy ends though so that is something that has a reasonable chance of doing well here.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-03, 07:57:01 PM
Seems like Skykomish x Galahad F1 would work well also. I don't think we can get Primabella easily in the United States.

Legend x Galahad F1 should also work well. Carol Deppe says in her book that Legend is PH2 homozygous.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-08, 05:00:09 PM
Ordered Galahad F1, Lizzano F1, and Purple Zebra F1 today from territorial. I went to visit family and ended up driving right past them for a job interview on a day they were closed! Timing wasn't right yet for 2022 seed racks in stores out there either! Nows the time for seed offerings.

https://eorganic.org/node/10822

Looking at this eorganic arcticle and going through my collection including recent acquisitions it seems like my late blight resistant collection might now include:

Skykomish
Iron Lady F1 and F2
Geranium Kiss-new
Stupice
Tigerella-new
Yellow Pear
Brandywine-new

Pending
Galahad F1
Lizzano F1
Purple Zebra F1
Cloudy Day F1

I don't expect much resistance from anything that doesn't have PH2 and PH3 but it is interesting to know that a few of the heirlooms are already known for small amounts of resistance. Given that my collection includes Solanum pimpinillifolium, Solanum habrochaites, Solanum pennellii, Solanum arcanum, Solanum galapagense, Solanum cheesemanii, and Solanum peruvianum as well as hybrids with habrochaites and pennellii I imagine there might be the possibility of some other resistance in there somewhere- actually I have a new strain of habrochaites... If I ended up moving to a more commonly infested area for teaching work it would be interesting to see what survived best. Or if one of the currently very rare late blight years hit my valley like it did in 2010 near here and 2015 near Bozeman MT.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Tim DH on 2022-01-10, 01:12:10 PM
Does anyone happen to know what the nature of Blight resistance in Stupice is? Our current choice of breeding material seems to be PH2, PH3 and Other. I'd be interested in increasing my sources of 'Other'!
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-10, 01:36:18 PM
Stupice is "other" but according to this https://blogs.cornell.edu/hort/2010/04/12/avoid-the-late-blight-blues/

It is two notches below Matt's wild cherry, yellow current, and yellow pear.

It could be that there is a PH6, PH7, and PH8 etc. out in the world somewhere. It could be that no one who is willing to share the info has shelled out to test some of the "other" types.

I think Carol wrote about her love of Stupice as an early that tastes good. I would think a reasoned course of action would be too cross Stupice and the other "other" resistance varieties with Ph2 and PH3 varieties. Maybe we would end up with some resistant varieties or even just open-source hybrids that would have a little extra ability to deal with late blight.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2022-01-10, 11:38:19 PM
I think there are some major dominant genes like Ph2 or Ph3 but for the most part LB resistance is multiple QTL and i guess this is the case of some heirlooms
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2022-01-11, 12:20:41 PM
Stupice do not show enough resistance in Netherlands.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-11, 12:22:40 PM
That makes sense if it is a third ranked tier in the article I linked. Have you tried any of the other heirloom types with "other" resistance Roland?
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Roland on 2022-01-11, 03:06:32 PM
Red Pearl in the verry wet 2021 year was not strong enough
Matt’s Wild Cherry good resistance
Mountain Magic verry good resistance

Rote Murmel was disapointing in 2021
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-11, 05:21:13 PM
I have been hearing good things about Matt's Wild Cherry for a long time now. I should probably put it on my wish list. It is pretty widely available.
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: nathanp on 2022-01-12, 05:50:24 AM
I have been hearing good things about Matt's Wild Cherry for a long time now. I should probably put it on my wish list. It is pretty widely available.

There are obviously other mechanisms for resistance other than Ph2, Ph3, and Ph5, they are just not understood or studied.  Matt's Wild Cherry may have one, as is also likely that some of Tom Wagner's lines do since they tested for greater resistance than could be expected with only Ph2 in that study referenced earlier.

Including tomatoes such as those probably makes sense for someone developing a breeding population then making selections out of it for best resistance.

A few others noted as having resistance out of traditional heirlooms are Wapsipinicon Pink and Pruden's Purple. 
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: Nicollas on 2022-01-15, 10:47:07 AM
About Purple Zebra F1:
Quote

Purple Zebra tomato is a fun new addition to striped tomatoes, producing tomatoes that are rich with complex flavors and a moderately firm texture. Dark red fruits with green stripes and a deep mahogany red interior do not produce muddy coloration like other tomatoes of this type. The taste is sweet and acidic leaning to sweet. Overall, this tomato has a better taste and thinner skin than comparisons with excellent disease resistance. Judges in the know say this is a very marketable fruit for farmers’ market growers. High disease resistance to ToMV, Verticillium Wilt Va/Vd, Fusarium Wilt Race 1, Leaf Mold A-E, Late Blight PH2/PH3, and intermediate resistance to TYLCV and TSWV.

“Flavor is rich, deep-bodied, almost dessert-like. Could go with vanilla ice cream. Very unique,” commented one judge. “The fruit was beautiful inside and out. They were orangy-red with green stripes and when cut diagonally, the interior was an especially attractive, juicy red,” mentioned another judge. “Good plant habit and disease resistance,” exclaimed another.
https://www.seedquest.com/mobile.php?type=news&id_article=134694&id_region&id_category&id_crop
Title: Re: Breeding for Late Blight Resistant Tomatoes
Post by: William S. on 2022-01-15, 11:18:31 AM
Nicollas,

I read that article! It is intriguing and Purple Zebra F1 should be an interesting variety to try. I got a message from Territorial seed that my Purple Zebra F1 seed should arrive today with Galahad F1 and Lizzano F1. It will be interesting next year to find out how they segregate. I would kind of expect the stripes to be stable and the color on Purple Zebra F1 but I doubt the precise flavor would be the same at all.