Is a non-astringent American-Asian hybrid persimmon within reach?

[jrd51]

Further to the above, a very good article on persimmon breeding:

Genetic Diversity and Breeding of Persimmon

<< Main objective of persimmon breeding has been to produce commercially attractive cultivars of the PCNA type which can be eaten without any postharvest treatment [[46]. Therefore, PCNA fruit are the most desirable for fresh consumption because it is not necessary to apply any postharvest treatment in order to remove the astringency. Hence, the breeding of new PCNA cultivars is the most popular objective in the entire persimmon growing countries. >>

<< Japanese PCNA cultivars are based on a recessive character and their genetic resources are very few. Repeated crossings within the narrow gene pool cause inbreeding depression, which hinders tree vigor, fruit yield and size. Therefore, studies have been ongoing to obtain new cultivars through the backcross (PCNA × non-PCNA) × PCNA since 1990. In 2007, ‘Taiten’ and ‘Taigetsu’, which are PVA cultivars, were derived from the cross of ‘Kurokuma’ (a local PVNA cultivar in Japan) × PCNA cultivar ‘Taishu’.

The proposed back-cross of JT-02 would be consistent with this (PCNA x non-PCNA) x PCNA paradigm. Yes, it crosses species but the hard part has been accomplished.

It would be very interesting to know whether the Japanese efforts with PCNA x non-PCNA kaki crosses have led to any successes other than the two PVA’s mentioned.

[murky]

Strange, why is the picture of almonds?

[jrd51]

LOL – I think it’s because the article was published as a chapter in a book with a broader theme. Unfortunately, the link to the book doesn’t give access to all pages.

[GeneH]

I would like to add to what Harbin has posted on the backstory to the Morris Burton persimmon.

I have been searching for some time for a contemporary newspaper report of the Burton persimmon winning the festival contest and just now found it, dated 30 Sept 1957. The fruit was entered by Samuel Oscar Burton (1886-1976) and named after his son Morris (1930-1976), a Korean War Vet. I am including here part of a 25 Sept 2012 newspaper article by Sam Burton´s granddaughter, Joyce Mundy.

[Barkslip]

Thank you Gene, thank you so much.

[Barkslip]

I’ve debated bringing this up since my first post about a week ago & the reason why Morris Burton is of “supreme” importance for (genes):

I don’t know what other literature suggests about the flowering of Morris Burton, but over the years… I’ve read the same; being’s Morris Burton is a male flowering throwing tree. Some people report they have never seen a single seed on their Morris Burton trees, however…

Those people are on this group.

Any clarification would be awesome for me to be able to put this subject to a final resting point.

Appreciate it,

Dax

[jrd51]

Dax –

What’s the plan to eliminate astringency? It seems that any astringent American x PCA Asian cross would be astringent. Ditto any cross of an astringent American x with an [astringent American x PCA Asian] hybrid.

The question boils down to: How do we get (a) American genes for cold hardiness and flavor, and (b) Asian PCNA genes for non-astringency into the same package -=- with the new hybrid homozygous for the recessive non-astringency gene? And why do the male flowers on Morris Burton help?

[Barkslip]

cause they told me that everything was female and I’d get no seeds. I read the thread about the GMO and that’s the winner, I understand.

From what I remembered when I jumped in this thing was that you all were thinkin’ (or so I guessed) that Morris Burton would be the likely choice due to its non-astringent characteristics. I misunderstood apparently how the genes play.

For my own information should I set up a Morris Burton next to (3) female hybrids and grow the seeds out myself, that’s where this comes back into play…

Dax

[jrd51]

I guess you’re assuming that Morris Burton is non-astringent when less-than-ripe. The comments from Jerry Lehman suggest that MB has “non-astringent characteristics” but I assumed that meant reliable non-astringency when fully ripe or very soon before.

Even assuming that Morris Burton is genetically non-astringent, there’s no reason to believe (is there?) that the genes are dominant. So crossing MB with an astringent hybrid will just produce another astringent hybrid.

It’s a long shot but your best bets might be:

(1) Morris Burton (male) x JT-02/Mikkusu (female). You might get something from the 5% subset of hybrids that combine three MB (non)-astringency genes with JT-02’s three PCNA non-astringency genes.

(2) Morris Burton (male) x Fuyu/Jiro (female). If this cross actually produces viable offspring, you’d have hybrids all of which combine three MB (non)-astringency genes with three PCNA non-astringency genes.

[Barkslip]

That’s what I thought. I thought Morris Burton had the capacity to when pollinating JT-02 could slide 3 genes and JT-02 also had a ‘3-gene’ rule I’m going to call it. ‘Sliding’ to 6 genes of recessive qualities to produce the non-astringent, types. So, am I fairly safe to say that Morris Burton or Taishu (pure kaki) could resultant a non-astringent persimmon whether crunchy or non-crunchy?

I know the number of 5% seedlings of Taishu crossed back to JT-02 or about 10-15 seedlings as Darryl Suggested is what would remain after the ones that were non-astringent were eliminated due to flavor. I know I didn’t write this easy to understand, so, I hope you are following my best attempt at trying to explain…

Edit:
And so to conclude my own thoughts, my best chances are to produce another astringent JT-02 type, right? I’d appreciate the feedback. We don’t need another… I won’t mess with it if that’s the case. thanks

[jrd51]

I’m not sure that I follow, but I’ll try to respond . . . .

JT-02 has 3 Japanese non-astringency genes from Taishu. These are recessive. Presumably JT-02 also has 3 American astringency genes from Josephine. I have no idea whether these are dominant, additive, recessive or what. I also have no idea whether they serve an analogous function. Non-astringency could, after all, result from different processes - a failure to make tannins, a failure to store tannins, a capacity to neutralize tannins once made, etc. We know, for example, that the Chinese PCNA variety Luo Tian Tian Shi achieves non-astringency somehow differently than the Japanese PCNAs (and that the gene is dominant).

Ideally in any cross with Morris Burton, JT-02 would contribute all 3 of its J_PCNA genes. We can estimate the probability that any one cross has all 3 genes as 50% (3 of 6 chance on 1st gene) x 40% (2 of 5 chance on 2nd gene, given success on 1st) x 25% (1 of 4 chance on 3rd gene, given success on 1st and 2nd). So 50% x 40% x 25% = 5%.

So 1 in 20 (5%) of these hybrids will have all 3 Asian non-astringency genes. Meanwhile they will also have 3 of 6 genes from Morris Burton. But AFAIK, we don’t really know anything about how these genes operate – whether they are dominant, recessive, additive, whatever; whether they are effectively the American counterpart to the Asian gene; or whether maybe they control some other aspect of astringency. So it’s a crap shoot.

I think the only sure approach to a non-astringent American-Asian hybrid is the one I described above – a back-cross of JT-02 with a J-PCNA variety, so that all 6 astringency genes are PCNA.

You might achieve the same result starting with Morris Burton rather than Josephine but you’d have to jump the hurdle of producing a viable offspring of MB x J-PCNA. You could, for example, go MB (female) x Taishu (male). Or you could go MB (male) x Jiro (female), maybe. In either case you’d then need a second cross with a male J-PCNA such as Taishu.

[Barkslip]

I’m setting this thread back and I understand…

You’ve already told me all this stuff or I concluded it earlier but I had hopes, I guess…

Thanks a lot!

Dax

@JustPeachy - I really appreciate everything you added to this thread… thanks.
@jrd51 - thanks a lot for reminding me about tannins and other things that could prove helpful…

[JustPeachy]

I think it’s just a matter of context. Let’s say we could get a nonastringent hybrid with reasonably good taste. Let’s also say it’s the size of Valeene Beauty (slightly smaller than a silver dollar) and is a shy cropper like Morris Burton. Would that be better for someone in 5b than an astringent JT-02 that is more than 3x the size and sets heavy crop?

I do agree that nonastringency is possible. I also think that it’s only important if you can conserve the traits of existing hybrids: size of fruit, heavy cropping, hardiness, vigor, etc…

Right now, the assumption is that you could create an nonastringent version of JT-02 with all the same characteristics for fruit size, cropping tendency, vigor, hardiness, etc… We all know that crosses don’t necessarily work that way. A successful cross often results in progeny where you gain one thing and lose another desirable trait; sometimes you even lose more than one desirable trait. Then you need backcrosses to reintroduce said loss trait, all hoping you maintain the original trait you bred into the first cross. Persimmons are more tricky because we are dealing with polyploidy. In pomology (apples, pears) and stone fruit (prunus), it’s really straight forward because it’s usually diploid, which is easy to work with. In persimmon, the polyploidy is the norm.

[Barkslip]

I totally agree and thank you for putting my mind to rest.

Thank you so much, Andrew!

Best regards,

Dax

[disc4tw]

I think that finding someone who has done research into the specifics of “which gene does what” would be helpful in this quest. I am betting Japan has the capability and funding to do so, but not the drive as they likely could care less for their own orchards whether hardiness increases.

The Russians, though, clearly have a vested interest and a history of attempting to improve cold hardiness and fruit size concurrently. I’m not saying we would need to partner with either, but having experts from either country as part of the discussion would probably be very helpful.

@jrd51

Non-astringency could, after all, result from different processes - a failure to make tannins, a failure to store tannins, a capacity to neutralize tannins once made, etc. We know, for example, that the Chinese PCNA variety Luo Tian Tian Shi achieves non-astringency somehow differently than the Japanese PCNAs (and that the gene is dominant).

This is very interesting information and probably some that needs to be considered for success without actual gene editing in a lab. Is it known what mechanism in DV or Hachiya causes astringency, and are they actually different genetics? If they are the same genes and we know they could be suppressed with certainty, then the quest is worthwhile.

I wonder if it would make sense to attempt crossing the Chinese LTTS with JT-02? If you have a higher probability of a dominant non-astringent gene being transferred that could then be bred with DV, would that make the odds drastically reduced and allow for selecting a better tasting seedling instead of hoping for a few that have the one trait you are attempting to replicate?

Would having a DV as the male or female be beneficial in either scenario in a series of back-crossing?

I’m mostly rambling but just trying to get some thoughts down before they disappear. I don’t have enough background in biology to figure this stuff out, just enough knowledge to get myself in trouble.

[jrd51]

@disc4tw –

<< I think that finding someone who has done research into the specifics of “which gene does what” would be helpful in this quest. >>

I have no evidence that such research exists yet.

<< The Russians, though, clearly have a vested interest and a history of attempting to improve cold hardiness and fruit size concurrently.>

Right but all the Ukrainian (not Russian) work has been with astringent varieties, Asian and American. Only the Japanese and Korean work focuses on non-astringents.

<< Is it known what mechanism in DV or Hachiya causes astringency, and are they actually different genetics? If they are the same genes and we know they could be suppressed with certainty, then the quest is worthwhile. >>

IDK. It seems that the mechanisms are different (maybe merely different tannins) because CO2 / alcohol treatment works in Asian PCAs but not in Americans.

I think a key question is whether the genes occupy the same spots on their respective chromosomes. So then is a hybrid either-or or both-and?

<< I wonder if it would make sense to attempt crossing the Chinese LTTS with JT-02? If you have a higher probability of a dominant non-astringent gene being transferred that could then be bred with DV, would that make the odds drastically reduced and allow for selecting a better tasting seedling instead of hoping for a few that have the one trait you are attempting to replicate? >>

When and if LTTS is available, I’m sure lots of growers would try crosses of LTTS with desirable varieties that would be improved by the removal of astringency. I have no idea whether LTTS produces male flowers. No doubt the crosses would be easier with Asian PCA Kakis than with Virgniana.

<< Would having a DV as the male or female be beneficial in either scenario in a series of back-crossing? >>

Almost all Asian PCNAs are female. Given that PCNA is recessive, that would be an insurmountable problem – all crosses would require a dominant astringent male – except that there are male flowers on a few PCNAs. So the few PCNAs that bear male flowers are very important. Taishu, which has been the pollen donor in most modern crosse, is monoecious. I believe that the same is true of some of the Goshos, which were used extensively in earlier work. Fuyu and Jiro produce some male flowers sometimes, but not routinely; so they have been used occasionally.

<< I’m mostly rambling but just trying to get some thoughts down before they disappear. I don’t have enough background in biology to figure this stuff out, just enough knowledge to get myself in trouble. >>

No worries. I’m only a step ahead.

[nosummer]

I would be interesting to see if the hermaphrodite traits that cause male flowers on some could be triggered to express in many more varieties, by using techniques like watering with colloidal silver during flowering.

These methods are well explored in cannabis breeding apparently for creating feminised seeds from two female parents.

Colloidal silver is easy to make overnight with a 9V battery and two pieces of silver if anyone wants to run an experiment on this.

[jrd51]

Some more info on PCNAs Fuyu & Jiro with male flowers . . . << Male flowers on these leading pollination-constant, non- astringent (PCNA) cultivars should be very useful for developing improved PCNA types >>

https://www.jstage.jst.go.jp/article/jjshs1925/64/1/64_1_41/_pdf

[disc4tw]

Another possibility - What if full Asian non-astringent seeds were trialed in the thousands to just find pure Asian cold hardy genetics? I know Miss Kim is supposed to be able to survive in z6B already. Why not get started on seeds there? Is there something I’m missing?

https://tropicalfruitforum.com/index.php?PHPSESSID=bac5cfa9e5e6d3a660a4ba145e582653&topic=30891.0
This crazy person is growing citrus in Pennsylvania. If that can be done, why not persimmons?

[Harbin]

This is one possible way but you need a good amount of pollen to create such quantity of seeds. Then the resulting seedling should grow in a harsh environment from the very beginning to speed up the selection for hardiness.