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

General Fruit Growing
#163

Dax – I think we don’t know a lot. But . . . .

  1. J-PCNA evidently become non-astringent by shutting down production of tannins early. I don’t think we have any idea whether the J-PCNA gene will operate the same way in American varieties. But it doesn’t seem intuitively unlikely. We need to try.

  2. C-PCNA evidently become non-astringent by triggering polymerization of tannins into insoluble molecules late. I don’t think we have any hard evidence as to whether the C-PCNA gene will operate the same in American varieties. BUT I have an educated guess:

The paper states, “Acetaldehyde is the product of pyruvate produced by glycolysis. As mentioned previously, acetaldehyde is one of the main compounds that render the soluble tannin insoluble and cause de-astringency.” So evidently C-PCNAs reduce astringency by producing acetaldehyde. Moreover, if my understanding is correct. PVAs and PVNAs reduce astringency (less or more) because the seeds make ethanol, which is readily converted to acetaldehyde. Finally, the paper shows that anoxia (water, CO2, alcohol) stimulates production of acetaldehyde, which is why it works to reduce astringency is PCAs and PVAs. Summing up – acetaldehyde is the key to removing astringency in Non-PCNA Kakis before fruit softening.

Now recall that anoxia treatments (water, CO2, ethanol) don’t work on American persimmons. This suggests to me that the C-PCNA mutation may have no impact in a hybrid C-PCNA x American. But again, we need to try.

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#164

Who the heck knows? A genome map.

Peace my brother(s),

Dax

#165

Is this Anoxia
Wild American Persimmon picked hard ,
and stored in fridge in plastic sealed bag a few months will ripen
This I am claiming first hand (but of coarse this is the internet)
I picked while other fruit on the tree was soft,
and ripe but low hanging fruit was hard
and a wild tree so from a 50 to 75 foot tree (or got what I could gather, but hard)

#166

That’s odd. This is the male tree that’s an offspring of Rosseyanka, or are you referring to Rosseyanka itself? Can you grow ones like Kasandra?

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#167

The Japanese released two crosses of Kurokuma (PVNA) x Taishu (PCNA). The two new varieties – Taiten & Taigetsu – are reported to be PVA.

The Koreans released two crosses of Johongsi (PCNA) x Nishimurawase (PVNA). Both new varieties – Chuyeon and Chosi – are reported to be non-astringent but the abstracts are not clear whether PCNA, PVA, or PVNA.

The PVNA trait is reportedly additive – the more ethanol produced by seeds the better (less astringent). I can imagine that a PCNA x PVNA cross is the worst of both worlds – not enough PCNA genes for the phenotype to be non-astringent, and not enough ethanol production by seeds to eliminate astringency.

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#168

There is indeed a PVNA hybrid though, one with kaki and virginiana lineage. Please reference this report.
https://www.facebook.com/350187278492088/posts/1316251648552308/

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#169

Hard to tell. I mean, there is anoxia but the cold itself may do something. We know that chilling will make a persimmon soft – that’s a problem for shipping fruit. I’m not aware that chilling eliminates astringency.

What I do know from serious experimentation is that the astringency in the American variety Prok is not materially impacted by ethanol. Also, I asked forum members for ANY experience showing that alcohol or CO2 works for Americans. Nobody produced any. Instead there were consistent reports of failure.

FWIW, even in Kakis there seems to be variability in the response to CO2. My understanding is that Triumph and Rojo Brillante were selected because they are very amenable, which makes them great candidates for commercial use of CO2 prior to shipping.

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#170

Were any of these actually released?

#171

Kasandra lives below snow at -9 F where the graft union was. 4 foot of strong growth all died right at the snow line.

I should’ve slowed down. I cannot grow the cultivar. Rosseyanka.

edit: didn’t read slow enough twice.

#172

Sorry to hear that…

How deep is your snow?

Scott

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#173

So maybe this is getting picky, but I can’t help myself: This “PVNA hybrid” is itself a cross between Costata (aka Picudo) and a hybrid. Cliff’s catalog described Pikudo as “astringent” – (“The fruit are of an astringent type”). Can anyone tell me definitively whether Costata / Picudo is PVA or PVNA?

FWIW, to me it sounds PVA. I suppose that leads me to wonder how two astringent parents can miraculously produce non-astringent offspring.

#174

That’s a great question. I was always under the impression that Picudo is PCA. There wasn’t a single seed in mine last year, so I can directly confirm it myself. Maybe more of my pollinators will flower this upcoming year, and we can make more firsthand observations. Whatever its lineage, that tree in question does look PVNA, and has survived some pretty cold temperatures at Cliff England’s orchard. It looks like something truly unique for those in zones too cold for typical non-astringent pure kaki.

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#175

That was 9" of snow about for Kasandra, Scott…

Dax

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#176

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.

#177

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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#178

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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#179

<< 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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#180

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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#181

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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#182

<< 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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