Hello everyone,
With my recent venture into tissue culture, I also have started reading up on embryo rescue which is actually very simple now that I have a tissue culture set up. I know they needed embryo rescue to create the first hybrid persimmon but does anyone know if they used a non astringent Asian variety to do so? I might be interested in trying to breed them.
Thanks!
I believe JT02 was a cross between Josephine and Taishu. And was embryo rescued. I assume they used pollen from Taishu male flowers which are known to occur but rarely.
Taishu is a PCNA kaki
Got it, I guess the astringency has more dominant characteristics then. Too bad. Thank you!
Yes, the non astringent trait is recessive and it is therefore difficult to get a non astringent hybrid persimmon by crossing with a PCNA kaki.
Japanese non-astringent is recessive. Chinese non-astringent is dominant. I’m not aware of any v X k hybrids which use the Chinese dominant gene.
Oh very interesting, any thoughts on what might be the best cultivar to play around with?
Luo Tian Tian Shi is one but hard to find in the U.S.
As discussed elsewhere, a back-cross of JT-02 (female) x Taishu (male) would appear to have a ~5% chance of producing a non-astringent offspring (6 recessive NA alleles). Since JT-02 is already a hybrid, embryo rescue should not be required.
It sounds like ideally I try and cross a dominant variety like this one with an American cultivar so that future hybrids that are generations down the line will be more likely to show a non astringency phenotype. If you have any information on where to get a Scion I’d appreciate it!
A few American growers have it. Maybe one will contact you by PM.
This is definitely an experiment worth trying. Just keep in mind that we don’t know enough to be certain that the allele that causes non-astringency in Chinese PCNAs will have the same impact in Americans.
For anyone thinking that the metabolic pathways must be nearly identical, I’d point out that whereas treatment with CO2 or ethanol tends to remove astringency in Asians (especially PVA Asians), it doesn’t seem to work in Americans. Or at least I know of no reports of success despite lots of attempts.
It’s not clear that Luotian Tianshi is entirely non astringent.
My reading of translated texts says that they need to be slightly soft to lose astringency entirely. Not the same as eating a crunchy apple.
Japanese PCNA are entirely astringency free when picked somewhat unripe. But in my opinion are also devoid of any flavor at that stage.
I think a non-astringent hybrid persimmon is the ultimate end goal but in a mean time We already got David Larvenge Kuninaja hybrid PVNA that you can eat rock firm and tasted great. In my opinion that PVNA always tasted better than PCNA anyway. Dax and I are growing around 50 seeds of Kujinaja X Open pollinated from Cliff England orchard and will see what we will get down the road.
Tony
Is PVNA a dominant trait?
ramv, that is complicated to answer. “NA” means non-astringent. The Japanese non astringent gene is recessive and requires 6 copies to be expressed. Chinese non-astringent is dominant and is expressed if one copy is present.
“PV” means pollination variant. If pollinated, the interior turns fully brown. I have not read recently on inheritance for PV so please look up some of the research which describes the trait. Brown fruit are considered extremely desirable in Japan. PV is a trait which is described as “xenia” which just means pollinating the seed shows up as a visible change in the fruit.
Darrell, I’m asking this in order to answer a simple question: if I plant a 100 seeds - one of whose parents is PVNA, how many offspring should I expect to have that are PVNA?
It is not academic, I actually have a hundred or so seeds one of whose parents is PVNA, the other is hybrid.
That is a very different question. If all the pollen producing trees are PVA, all offspring will be astringent though some may express the pollination variant trait of brown fruit.
From a breeding perspective:
if both parents are JPVNA, the offspring will all be JPVNA.
If one parent is PVA and one is JPVNA, all offspring will express PVA.
If one parent is JPVNA and the other parent is an F1 such as JT-02, offspring will segregate with somewhere between 3% and 8% of offspring being JPVNA. I’m being very careful with this answer because part of the known inheritance pattern suggests a steering structure during meiosis which may make 3 PVNA genes more likely. Wheat uses a steering structure which has been described in several research documents. Wheat is a hexaploid with some similarities to hexaploid persimmon.
I have a very different answer. It is based on my interpretation of some published breeding experiments. I asked myself, “For these results to make sense, what must the genetics of the PVNA trait be?”
The results suggested to me that a persimmon with 1 PVA allele (out of of 6) displays a PVA phenotype; a persimmon with 2 or more PVA alleles displays a PVNA phenotype.
The Japanese breeding program released two PVA types that were crosses of PVNA x PCNA, which tends to support the view that PVA is just a diluted version of PVNA.
[Note that some PCNA varieties (Izu, Fuyu, Okugosho) appear to hold some PVNA alleles. The cross-breeding results suggest to me that Izu has two PVNA alleles whereas Fuyu and Okugosho have one. The result is some browning of seeded fruit in these PCNAs.]
@Fusion_power – can you provide references to research on the “known inheritance pattern?” Thx.
@jrd51, what would your number be then?
Since I will soon have one or more PVNA hybrids, I expect to have fruits that have both parents as PVNA and that will hopefully explode the number of PVNA varieties available.
If sorting is random, then I’d think of this as a problem in binomial probability. And I start with the inference that a PVNA pollinator probably has 2 PVA alleles, though some varieties might have more.
So assume a bin with 4 red balls (PCA) and 2 white balls (PVA). Select 3 balls. What are the odds that the three selected balls include 1 red and 2 white, where two PVA alleles would express as the PVNA trait. The answer is 20%.
I have no idea if sorting in persimmons is random.
p.s. If I did the math right, you’d get 60% PVAs.
Ramv wants both PV and NA. NA has known recessive inheritance. PV seems to behave more as a penetrant trait meaning as more PV alleles are added more PV phenotype is expressed. Hence my answer of 2 to 8 percent would show PVNA. Please note the example of JT-02 which is a hybrid of Josephine X Taishu. It is presumed to be 3 non-astringent alleles and 3 astringent plus 3 pollination variant alleles with 3 pollination constant alleles. I have however not attempted to prove this via existing research. I’m going on memory.
If ramv has 100 seed representing the above parentage, it is highly likely he will get a few PVNA offspring. It is also guaranteed most of them won’t be PVNA.
