Disease resistance: Liberty vs. Freedom apples

Bob…what was the variety you got from ARS this year that is supposed to be insect resistant?

Did you share that with me? If so, I have it grafted. I’ll be excited if it’s one I have grafted.

What product and when do you spray for CAR blueberry? Have you ever had CAR on any of your Goldrush?

I think you may be onto something there which would also explain the good reviews from knowledgeable growers in southern climes.

Even if you get the brix up, it is a “light” apple as opposed to dense fleshed. I prefer dense apples as a rule, but that is entirely up to the individual palate. Probably most people prefer a denser apple for cooking, though, because they tend to hold their texture better.

That was a very thoughtful evaluation you did, by the way. As you probably know, apples in the shaded part of the tree are usually of worse quality regardless of variety, but naturally high brix apple varieties seem to fare better. Back in the day when I was a sweet apple lover I would buy Fuji apples from a local grower (this is in NY). It was the only apple that had nice tasting “B” apples. I’d buy a bushel of poorly colored, smaller Fujis at half price.

I try to train apple trees so there are no shaded parts. Your idea about an espalier increasing brix can be correct, as long as their are enough supporting leaves for each fruit.

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I just read the exchange between me and ApS. Before doing so I thought he was almost entirely to blame for all the noise, but actually I set him off after he contradicted me by my unconscious sarcastic tone. I do become even more of an AH in Spring. I’m working 14 hour days and still maintaining my addiction to this forum. I get resentful when I feel my time is being wasted, even if that is an arrogant attitude. Sometimes people write carelessly, myself included.

I believe he was careless in his statement of disagreement- turns out he was apparently talking about FB which hadn’t even been in the discussion. The program to develop the official DRs was about scab, CAR and mildew, as I understand it, and until resistance becomes an issue, 2 or 3 applications of myclobutanil should completely control them. These apps do coincide with insect sprays in most regions where at least the first two are a problem.

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Bob

I have quite a few heritage variety popular in the south but the results are mixed as far as FB.

FB was terrible on Old Fashioned Winesap, but it barely touched the Virginia Winesap, The FB resistance charts don’t distinguish between the two Winesaps, but they are very different. Stayman which is another popular apple in the south also got hit hard. Summer Rambo was hit so hard, most of the trees died. I only have a few S Limbertwigs, and they did about average. Grimes were a little worse than average.

One year of results on young trees is not enough data to draw perfect conclusions, but its interesting that the infection rates that I experienced were different what what I expected.

I don’t mean to dismiss the university guidelines. The research has been very useful to me and I continue to use it, but the results on my farm do not always agree with the research - even the research done in my state.

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Yes, Williams Pride had very clean leaves, even at the end of September, a month after I picked the last apples from it. It has a great return bloom this year.

Several other DR’s did very well, especially Priscilla and Sundance. Both are listed by Purdue as resistant to Scab, Fireblight, and CAR.

I know Priscilla got a bad reputation on fruit quality, but I find it pretty good. It has a sweet, interesting flavor which most people seem to like. The one problem I’ve seen with it is that it can get soft if you wait too long. So for me, it is more a late August apple, than the September it is advertised as.

Sundance it a bit like Goldrush in that it is very acidic off the tree, except that it is harsher. SD really needs some aging, but it keeps very well. I saved a half dozen or so and they were very good after a couple months. I think that I’ve still got one in the fridge, which I should try soon.

Some of the old varieties also had very clean leaves. In particular, Old Nonpareil, Court Pendu Plat, St Edumunds Russet, and Ross Nonpareil. The full list is here.

I started out just bagging, then switched to spraying Surround last spring. This year I’ll probably go back to bagging more and finish up my package of Surround. I’m planning to do an early summer fungicide for peaches, as the rot I got on NJF 16 was horrible last year. Given the bloom on the tree, I can get a bumper crop if I can protect them.

Here’s a GW post where insect resistance was discussed. I sent you PRI 672, a scab resistant Golden Delicious type with 17.9 brix. You ordered PRI 996 from ARS yourself- that’s the one with Scab and PC resistance, whose brix measured 17.3.

I agree- I put almost the same caveat on my Apple leaf report post. But it is still interesting. From what others have said on the board, fireblight in particular can be particularly capricious, as diseases go, striking where you wouldn’t expect it. Thankfully, I haven’t been hit by it at all yet (knocks on wood…).

Looking at my note, I see “crunchy” appearing several times for Liberty. I also have a vague recollection that the texture itself was different between the high and low brix areas. I’ll keep an eye on it this year.

My tree is on G65 and thus so small that there isn’t much in the way of shaded parts. In the case of the above apple, part of it was covered by leaves. One wouldn’t think that would matter so much, as those leaves should be feeding the apple. But, it appears that the apple either makes use of the sunlight, or it creates a condition within the apple which leads to sugar development.

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The spur leaves and nearby shoot leaves create most of the sugar from my reading although the fruits skin contains chlorophyll and contributes. . There is a point where the energy goes up instead of down but I don’t know where the line is, but figure an apple needs about 30 well lit leaves. That, at least, is the often repeated dictum.

Wrong.

Fireblight resistance served as the cornerstone of DR breeding.

Almost all the DR programs were in fact, first and foremost, for fireblight resistance. Of course scab etc were obviously goals as well, but the foundation was based off of fireblight resistance.
Proof of that is the use of Malus Floribunda to introduce the VF gene for fireblight resistance. Mildew and even CAR seem to have taken a back seat to Fireblight and Scab, and really not given much priority in DR breeding.

There may be some DR varieties which do not have MF 821 in their parentage, and probably are, but the vast majority do. Maybe all of them do.

I wasn’t aware of any link between the VF gene and fireblight resistance. I think FB is part of what they will test DR candidates for, but it isn’t directly from the VF gene.

Here’s a reference, which describes the lack of correlation (page 263 if it didn’t come through on the link).

You’re right Bob…I stand corrected on the vf aspect of my statement it is attributed to scab resistance, though maybe not entirely(for the vf gene). Malus floribunda 821 is however used, or has been, in breeding for fireblight resistance. It is used in every single apple mentioned in this thread, Goldrush. Priscilla, William’s Pride, Freedom and Liberty. I suspect it was used as a catalyst for resistance to scab via the vf gene and fireblight via QTL.

I did a ton of research for this reply, and to be honest, everytime I look into the breeding aspect, I’m amazed at just how complex it all is. It seems there are at least three other sources (and by that I mean in both direct and hybridized complex-cross usage) for fireblight resistance. Malus Evereste has apparently showed modest improvements over 821 in FB resistance in several trials I studied.
Interestingly enough btw, Mildew resistance (at least in early going, perhaps altogether) came also by way of the vf gene. It seems that whatever quality that is invoked in providing scab protection just so happens to provide significant mildew resistance.

Here is a short abstract from research that states it somewhat clearly without being too detailed. It is interesting to note that it is published by Dresden-Pillnitz Germany which was referred to in your link.

Fire blight, caused by the bacterium Erwinia amylovora, is one of the most destructive diseases of apple (Malus ×domestica) worldwide. No major, qualitative gene for resistance to this disease has been identified so far in apple. A quantitative trait locus (QTL) analysis was performed in two F1 progenies derived from two controled crosses: one between the susceptible rootstock cultivar ‘MM106’ and the resistant ornamental cultivar ‘Evereste’ and the other one between the moderately susceptible cultivar ‘Golden Delicious’ and the wild apple Malus floribunda clone 821, with unknown level of fire blight resistance. Both progenies were inoculated in the greenhouse with the same reference strain of E. amylovora. The length of stem necrosis was scored 7 and 14 days after inoculation. A strong QTL effect was identified in both ‘Evereste’ and M. floribunda 821 at a similar position on the distal region of linkage group 12 of the apple genome. From 50% to 70% of the phenotypic variation was explained by the QTL in ‘Evereste’ progeny according to the scored trait. More than 40% of the phenotypic variation was explained by the M. floribunda QTL in the second progeny. It was shown that ‘Evereste’ and M. floribunda 821 carried distinct QTL alleles at that genomic position. A small additional QTL was identified in ‘Evereste’ on linkage group 15, which explained about 6% of the phenotypic variation. Although it was not possible to confirm whether or not ‘Evereste’ and M. floribunda QTL belonged to the same locus or two distinct closely related loci, these QTL can be valuable targets in marker-assisted selection to obtain fire blight resistant apple cultivars and form a starting point for discovering the function of the genes controlling apple fire blight resistance.

Interesting to me that they chose MM106 and Golden Delicious as the candidates to cross with. I can only assume that it is done so as to more easily ascertain if indeed, the FB resistance has been passed along when the inoculum is introduced.
It may also be due to the reasonable assumption that FB resistance may be a dominant allele and in this way would be more likely to be expressed in the progeny.

In 25 years of managing orchards in the northeast, FB has never become a serious issue with apples on the free standing trees I manage- not at a single site, beyond cutting some strikes from trees. That is probably why I didn’t recall any information about FB resistance I may have read when I was determining the use of the likes of Liberty and Williams Pride in my nursery.

This really isn’t about winning debates so much as providing useful information. For more southern growers and even growers in regions such as the northeast, where in some districts FB was very bad in apples last year and possibly this one, FB resistance may be an important issue- it is much harder to control than scab or CAR and requires a separate regimen.

Here is a chart provided by Purdue with actionable information.

I have a list of varieties evaluated by Tom Burford (a well known apple guru with decades of experience in VA) for FB resistance and it is interesting how his experience does not coincide with Purdue’s chart.

Burford suggests “old strain” Stayman is resistant, for instance, and Purdue calls it susceptible. I only mention this to suggest that even in areas with high FB potential, cultivars considered susceptible may turn out to be OK for someone wanting to experiment. Burford also suggests resistance in old strain Winesap which, on this thread, was said to be false where wood I had provided of this strain was severely struck.

I think the DR’s known for FB resistance.would be the superior choice as the mother of multigrafted trees in regions and districts with a high FB issue. This might stop minor strikes from becoming big problems.

There are far more interesting (to my palate) varieties than Liberty to turn to for FB resistance, but my key objection to it as a mother tree is that it is a poorly structured tree that I find difficult to shape into an efficient form. I think William’s Pride might be a better choice.

Not sure about old strain Stayman, but in my case it was Virginia Winesap that was almost immune to FB, where the Old Fashioned Winesap got clobbered. I believe the Old Fashioned Winesap may be the original Winesap from NJ. The Virginia Winesap was discovered in an orchard in Troutville, VA in the early 1900’s.

I attended a seminar taught by Tom Burford several years ago and his suggestion for an orchard in my area of NC was Winesap and Grimes. I did plant the variety he suggested, but the concentration in just two variety did not suit my plan.

It has not been discussed, but the rootstock and the age of the tree may be more important FB considerations than variety. My young trees on B9 are a lot more susceptible to FB than the older trees on MM111. When I had the major FB outbreak last year, I only had a few strikes on the MM111 trees.

Even after the major FB outbreak last year, I believe I missed most of the blight this year! I sprayed strep a total of 6 times based on the predictions of the Maryblight computer model. I also had to increase the rate of strep slightly in order to get the leaf burn I was looking for.

When did you speak to Burford? On the list I have which he made back in '03, he didn’t distinguish between Winesaps beyond writing “old strain”. His entire list of FB resistant apples include Arkansas Black, Ben Davis,Black Twig, Detroit Red, Empire, Fameuse, Grimes Golden, Kidd’s Orange Red, King David, Kinnard’s Choice, Liberty, Maiden Blush, Macintosh, Smokehouse, Spartan, Spigold, Stayman, Summer Rambo, Virginia Beauty, Wickson Crab and Winesap.

Alan

Spoke with him about 4 years ago at a seminar held at Vintage Virginia Apples, just outside of Charlottesville VA. Its actually Lee Calhoon and David Vernon that draw the distinction between the two Winesaps Lee in his book “Old Southern Apples” and David in his catalog of apple trees for Century Farm Orchards.

On another note: A well know family of Apple/Peach growers with the last name Haight moved to my area of NC from Westchester County about 30 years ago. They sold their orchard in NY to get away from the high taxes. Not many orchards in my area - but these folks grow great peaches/apples. Any chance they are related to you?

No, but I know their orchard site well and people often ask me that- but the T at the end changes everything.

Thanks for the info about Virginia Winesap. How does it taste?

The Vintage Apple people were and probably still are associated with NAFEX. I was there years back at a NAFEX annual meeting. They seemed very nice people. That was the first time I met Burford as well.

I much prefer the taste of Stayman compared to either one of the Winesaps, but I like the Va Winesap better the the Old Fashion Winesap. I rate the taste of bothWinesap as OK, but not great

The people for Vintage Virginia Apples now have a big presence in the hard cider business, I believe they are called Albemarle Cider Works and they are located not too far from Monticello, which has got to help

Burford and a fellow from Penn State taught the 1 day class in Apple Orchard Production when I attended a few years back. I noticed Burford indicated Summer Rambo had a high degree of FB tolerance. I found it be be highly susceptible, similar to Lodi. I removed all of them along with all of my Lodi.

Winesap gets a nice flavor here, but ripens in cooler weather so that may help. Stayman is similar but sweeter. They both are great producers.

Alan writes thusly:

I have a list of varieties evaluated by Tom Burford (a well known apple guru with decades of experience in VA) for FB resistance and it is interesting how his experience does not coincide with Purdue’s chart.
Burford suggests “old strain” Stayman is resistant, for instance, and Purdue calls it susceptible. I only mention this to suggest that even in areas with high FB potential, cultivars considered susceptible may turn out to be OK for someone wanting to experiment. Burford also suggests resistance in old strain Winesap which, on this thread, was said to be false where wood I had provided of this strain was severely struck.

Over the years, Ed Fackler,among others have come to believe their are different strains of fireblight. That may explain the regional results.

For example,in pears,I simply have not been able to keep Magness alive,fire blight claims it all the time,which is rather shocking but blight susceptible varieties chug along oblivious right next to it.

the fluffy one

Thanks everyone for the excellent post on this topic.

I purchased my Liberties when I just started growing and when reading about them had visions of perfect apples without spraying. The reality is much different and if I could go back would not have planted three of them. I would not want a lot of them because they throw out a lot of wood and are more difficult to prune especially for an amateur. Just from postings I think maybe Liberty is a better Apple I sure like it and appreciate it more often than less. One thing I think about disease resistant trees is if I have a year that for some unforeseen reason I don’t spray I still may get a few good apples from my little orchard.