@ZinHead – Exactly! That’s why I’m so focused on JT-02. It’s father was the Asian PCNA variety Taishu. So presumably, JT-02 has 3 recessive (Asian) PCNA genes and 3 dominant (American) non-PCNA genes. With a single back-cross of JT-02, we can have offspring with 6 recessive PCNA genes. Voila!
The proportion of PCNA offspring should be approximately 3/6 x 2/5 x 1/4 = 5%.
Okay, good point.
Further explanation of the role of copper:
It boosts a plants ability to do an (immune system response) to insects & disease.
When a plants leaves are eaten, it stimulates an immune system response.
During an immune system response (tannins, methoxypyrazines & pheromones) get manufactured at higher levels.
The pheromones can actually trigger an adjacent plant to also manufacture additional tannins.
Understood.
Hope you are successful.
I will be in line to buy.
Meanwhile I’m rolling the big boulders uphill.
LOL.
OK, got it re copper.
On the JT-02 backcross, I made it clear when I started the other more relevant thread that I was proposing work for someone else. I have no plan to breed trees myself. So I’ll be in line right behind you.
Lots of persimmon threads.
Which one?
Okay, thanks
@Barkslip
Hum,
Have great interest in the varietals,
but not in a position to purchase at present.
My funds for the rest of this year are going into Asimina triloba.
Hopefully, this is an on going thing?
no.
I’m a hobbyist grafter. If I decide later in the future to graft again, then I will. I don’t have plans to do so. You better learn to graft and trade wood with the folks buying my trees so you know the rare stuff has come from ortet trees and those that have fruited already from collectors. Or, you never know what you may get. I’ve spent my whole life garnering a reputation as a plantsman…
Thanks for your interest. That’s the end of the story.
B-slip
I don’t think this paper changes anything. I’ve read it before. Admittedly, it’s a bit above my pay grade. Even so, it’s easy to extract some key points. The persimmon-growing industry consider PCNA to be superior, perhaps largely because there is no need for special effort to remove astringency. But the PCNA gene pool is small and in-bred, so it is hard to change traits such as taste without cross-breeding to PCAs. But the PCNA trait is recessive so multiple generations are required; the F1 generation produces no PCNA offspring. Bottom line, the industry would welcome hybridization with PCAs – if they can retain the PCNA trait. The main point of the article is that the time-consuming process can be accelerated with the use of markers for the PCNA gene(s).
For me, the most interesting tidbit is the inference that PCAs may not be homozygous. To my naive mind, this makes sense if PCAs and PCNAs are crossing in the wild. Since tannins are an adaptation to repel fruit-eating creatures before seeds have ripened, I find it easy to imagine that PCAs have a reproductive advantage – at least until humans discovered and started cloning them.
Any PCA that is heterozygous would produce a higher proportion of PCNA offspring in a PCA x PCNA cross.
This is a pretty good summary of persimmon breeding and a fairly good discussion of potential. There is a dendrogram of common persimmon cultivars in one of the tables. D. lotus and D. virginiana are on the extreme right and show high similarity to each other. This is suggestive that D. virginiana diverged from D. Lotus in the not too distant past. While the dendrogram is useful, it is based on morphological traits so is not as reliable as if it were from genetics.
@ZinHead
Absence of copper will cause a reduction of female fertility in perennial fruiting plants. Any recommendations about copper should include specific dosages.
If true, then I believe it would have occurred prior to recent cross-Atlantic continental collisions.
I’m very aware of what Copper’s functions are & the importance of copper in photosynthesis.
I wasn’t making any recommendations or diagnosing any plants.
@ZinHead
I was referring to this advice:
… and was not referring to the role of copper in photosynthesis.
It’s a statement of fact, nothing more.
Copper spray is near religiously used as an organic disease control especially in Vitis vinifera.
One of the main problems which results from its use is that tannins in seeds, skins & stems are still high with seeds & stems still green, when target brix is achieved.
@ZinHead
Copper pesticides for disease control come in several chemical formulations - as do water acidification products containing sulfur. Your general statement “Copper spray for diseases slows ripening” is only true for some of them above certain dosage levels and there are at least two known to myself and others at GrowingFruit which would require such a massive overdose that the plant would likely die in the process. The necessary dosages for the rest of them vary by plant sub-tribe. If you cannot provide the specific formulations and accompanying dosages that would interfere with ripening, then for the benefit of novice readers I recommend you delete your post above and refrain from making unquantified recommendations in the future.
Copper plays a major role in Iron assimilation, indirectly resulting in extra Cytokinins from roots & Auxin from young leaves.
This plays a role both in more female flowers of higher fertility as you mentioned, but also increased vegetative growth, plus increased (Methoxypyrazines & tannins), as ethylene as turning the starch into sugar.
If insects attack the plant near fruit ripening, there will be an increased auto immune system response of even more tannins, plus pheromones which will trigger adjacent plants to do the same, even if not being eaten.
If there are forms of Copper which don’t do this, please itemize them.
I didn’t make a recommendation.
I stated a fact & what I personally do on a property that is copper toxic.
Increased Copper results Increased Iron assimilation, Increased Iron results in Increased Chlorophyll-A, Increased Chlorophyll-A results in Increased Auxin from young leaves, Increased Auxin results in Increased Cytokinins from roots, Increased Cytokinins results in tannins not ripening.
Please itemize the Copper sprays vetted to not do this, if such exists.
I’m not deleting an accurate factual statement!