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

So I’ll go back to asking what may seem like an obvious question…

If the C-PCNA and J-PCNA genes are different, wouldn’t it behoove us to cross both of them to gain BOTH sets of non-astringent genes in one “super Asian persimmon”? I would hypothesize that having both dominant AND recessive genes exhibiting half of the traits we desire (cold hardy /non-astringent) would make the task of selecting for a better tasting/larger hybrid more successful.

Further- for the sake of speeding up the process and making it less complicated if breeding in colder zones, would it make sense to begin with a cross of DV & C-PCNA as C is dominant, then back cross to J-PCNA for improvement? Am I over thinking this? Should J-PCNA even be included?

Based on what I have read, it seems J-PCNA is preferred due to better taste, however if DV is a great improvement in taste, maybe it will make an exceptional hybrid simply with the dominant genes of C-PCNA…

I also wanted to point out - just because the big operations use thousands of trees to select one good tree, that doesn’t mean that a planting of 200 wouldn’t produce one amazing tree, it’s just statistically less likely.

An aside - having concurrent trials for gaining better Asian genetics and then crossing those in a colder zone as a “sister project” seems to be a good way to move forward if possible… None of us are getting any younger.

My 2 cents:

<< If the C-PCNA and J-PCNA genes are different, wouldn’t it behoove us to cross both of them to gain BOTH sets of non-astringent genes in one “super Asian persimmon”? I would hypothesize that having both dominant AND recessive genes exhibiting half of the traits we desire (cold hardy /non-astringent) would make the task of selecting for a better tasting/larger hybrid more successful. >>

To produce fruit for eating, I don’t see the point. You just need one viable path to non-astringency.

To produce cultivars for breeding, we need to maximize the odds of getting the right genes in the right places. So I think we mostly need (1) a male-flowering J-PCNA (e.g., Taishu) with good fruit characteristics, and (2) a male-flowering C-PCNA with as many non-astringency genes as possible. By necessity, the J-PCNA would be homozygous. Ideally, the breeding C-PCNA would be also homozygous. #1 is required to propagate ANY non-astringent variety based on the recessive J-PCNA gene. #2 is required to increase the proportion of non-astringent hybrids that would result from crosses.

<< Further- for the sake of speeding up the process and making it less complicated if breeding in colder zones, would it make sense to begin with a cross of DV & C-PCNA as C is dominant, then back cross to J-PCNA for improvement? Am I over thinking this? Should J-PCNA even be included? >>

There are two strategies, I think: (1) As discussed above, generate a F1 cross of DV x J-PCNA (e.g., Josephine x Taishu); then generate an F-2 back-cross x J-PCNA. A small proportion of the hybrids should be non-astringent. (2) Generate a F1 cross of DV x C-PCNA. A high proportion of the hybrids should be non-astringent. Either/or works. Both/and seems unhelpful.

<< Based on what I have read, it seems J-PCNA is preferred due to better taste, however if DV is a great improvement in taste, maybe it will make an exceptional hybrid simply with the dominant genes of C-PCNA… >>

Sure. We won’t know unless we try.

To create an improved Kaki, it seems the most efficient approach would be to cross a tasty, astringent variety PCA /PVA variety x a C-PCNA variety. The 1st generation might be great. If not, and if we could get 2-3 C-PCNA genes into that F1 cross, then it would be efficient to re-cross the hybrid with another tasty astringent variety. So we might quickly produce a non-astringent Saiyo or Hachiya.

To create an improved Virginiana, it’s critical to know how J-PCNA and C-PCNA genes will operate in a Virginiana cross. If the J-PCNA genes can curtail the production of tannins in a hybrid, then the F2 generation (e.g., JT-02 x Taishu) could succeed. If the C-PCNA genes can render those tannins insoluble, then the F1 generation (e.g., Barbra’s Blush x Luo Tian Tian Shi) could succeed.

<< I also wanted to point out - just because the big operations use thousands of trees to select one good tree, that doesn’t mean that a planting of 200 wouldn’t produce one amazing tree, it’s just statistically less likely. >>

Right. It’s a lottery.

<< An aside - having concurrent trials for gaining better Asian genetics and then crossing those in a colder zone as a “sister project” seems to be a good way to move forward if possible… None of us are getting any younger. >>

I just turned 70, so I agree wholeheartedly. If it works, the cross described above of C-PCNA x DV would be the most direct approach. That would get non-astringency from the C-PCNA and cold hardiness from the DV. If other attributes such as size and flavor need further improvement, the next step would probably be a cross of the hybrid x a large, tasty astringent Kaki.

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To the best I can tell, there are no synergies to be gained from combining the NA genes. However, there is very high potential when crossing a very good flavored DV with a large fruited CPCNA or JPCNA. Keep in mind that this would have to be done via a bridge cross (X an existing (DK X DV) hybrid) to make it work.

Since JT02 represents a combination with both DV and DK PCNA, it looks to have 1/2 of the required genetics. What is needed is a high quality mate with compatible background genetics.

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<< Since JT02 represents a combination with both DV and DK PCNA, it looks to have 1/2 of the required genetics. What is needed is a high quality mate with compatible background genetics. >>

Right. As I said above, that would be a J-PCNA. There are only so many possibilities that produce male flowers. The “father” of JT-02 – Taishu – seems the best choice. Its ancestors are Fuyu, Jiro, Okugosho and Hanagosho.

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Backcrossing to the parent might work up to a point, but my experience is that out-crossers like persimmon develop problems when inbred.

I would love to see a way forward that involves more American genetics.

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Morris Burton is involved in all of the 4 varieties that were observed to produce what Martha Davis and I call non-astringent fruit. That is some of the fruits could be picked off the tree while still firm with no astringency. Those 4 varieties were L-92, L-93, L-104 and L-104A. Morris Burton is involved in all 4 of these. L-92 and L-93 are Szukis X F-100. L-104 and L-104A are F-7 X Killen (using female pollen).

We have some options, albeit from the same parent (Morris Burton). I wonder if any other varieties (male or female) have been tested for the same traits

(from the thread started by @SMC_zone6)

Surely if Morris Burton was a seedling found in a field, there have to be other trees exhibiting similar traits. Maybe we need to have a call to action for those who live in the northern zone to test local trees for less astringency early in the season. Not a necessarily enjoyable task but one that would benefit the cause.

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<< we need to have a call to action for those who live in the northern zone to test local trees for less astringency early in the season. >>

I’m all for the effort. Who knows, we might find the American equivalent of Gosho in Japan or Luo Tian Tian Shi in China – a genetically non-astringent fruit.

Meanwhile, I’m cautioned by the phrase “some of the fruits.” It seems that non-astringency is not a reliable result.

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Yeah, Japanese and Korean breeders have long complained about the adverse results of inbreeding among J-PCNA varieties, which started out inbred and just get worse with every J-PCNA x J-PCNA cross. And decades of breeding have seemingly produced very few significant improvements over Fuyu, Jiro, and their bud sports.

I’d love to see what happens with a back-cross of JT-02 x Taishu (J-PCNA). We’re so close, and both varieties taste good. But the fast track to a non-astringent persimmon with “more American genetics” would be through the C-PCNAs – IF . . . IF . . . IF the C-PCNA gene works in D.V.

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See Fig 3 & 4 to get a sense for how inbred J-PCNA hybrids are. Everything displayed traces back to Jiro, Fuyu (and a budsport), Okugosho, Hanagosho, and Fukurogosho.

FWIW, my own reading of release reports suggests that the best choice for short-season growers is Soshu, but I have no data on cold-tolerance.

Persimmon Breeding Japan PCNA.pdf (717.3 KB)

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From an uneducated perspective, adding DV to the genetics should drastically reduce the amount of any inbreeding issues, correct? Even if it was a few related DV crosses?

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Very much, yes. Here’s the first diagram I know of that started it all:

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Exactly! That’s why I’m is excited about JT-02 and its prospects.

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Reading some of the linked articles confirmed my speculation that inbreeding would be a problem. Yes, in any cross with DV x DK, inbreeding would be at a minimum, however, this cross is far enough apart that there would be genetic issues to resolve which could include chromosome inversions, translocations, and fertility problems.

Based on current information, Morris Burton, Prok, and Early Golden (or offspring) have very high potential in crosses with DK. Morris Burton because it brings a novel NA trait into the mix. Prok because it brings very large size. Early Golden for fruiting and flavor traits and tendency to produce male flowers. I don’t know the genetics behind the Russian made crosses between DV and DK so it is hard to say if they carry enough potential. IMO, the necessary genetics are available to make some potentially major improvements, but they are still locked up in different species and particularly locked up in female only varieties where a male is needed to make useful crosses.

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I concluded Prok today. Unlike @jrd51 I have eaten Prok before it was fully ripe and it had some hard aspects to its fruit off the tree as I picked and ate it. It was not-astringent.

Unfortunately I don’t have it in my yard, but… at Red Fern Farm this happened on many Prok’s I ate during one summer visit of several visits.

Sept. 11th I was picking and eating Prok:

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Prok is not large. It may be large relative to the average wild American – it’s the only American I grow, so I can’t be sure – but it is small relative to Asians. My IKKJs seem 3-4 times as large. JT-02 appears 2-3 times as large.

Early Golden is reported to be the American variety used in Ukrainian hybrids. I’m not aware of any disclosures about variety names of either DV or DK parents.

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2" is very large for American persimmons.

Maybe something about your growing conditions caused a radical difference. If so, that would be more valuable to know than anything about persimmon genetics.

FWIW., my Prok begins to ripen in late September and continues through November. Any even slightly unripe fruit are so astringent that you can’t spit hard enough. Your tongue, cheeks and teeth get coated with a sticky sediment. It’s not just me – I’ve had at least a dozen people try the fruits at full ripeness plus or minus a little.

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I best confirm my thoughts with Tom Wahl at Red Fern. Alright, thank you.

Nope, Tom doesn’t think I know what the hell I’m talking about.

He said, “There is a firm (but not crunchy), non-astringent persimmon called Geneva Long. It is one of the few that can be sliced like a tomato when it is ripe and ready to eat. It is probably very hardy, too, as it was bred in New York. That might be the one you’re looking for, for breeding purposes.” (Tom Wahl)

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Well, I REALLY appreciate your honesty. It certainly saves us time arguing about misconceptions. And I’m very relieved. Thank you.

Tom is probably right about using Geneva Long for breeding. Has it never been done before? I’ll have to think about the implications.

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