Tropical Fruit Forum - International Tropical Fruit Growers



Author Topic: Yuzu Ichang Papeda cross  (Read 2617 times)

Till

  • Member
  • ***
  • Posts: 34
    • Germany, Simmerath (City), Zone 6b
    • View Profile
Re: Yuzu Ichang Papeda cross
« Reply #25 on: December 09, 2020, 02:35:09 PM »
You read it everywhere that Yuzu is a hybrid of Ichang Papeda. But genetic studies are not in favor of that constantly repeated supposition. I have an article in mind that demonstrated that Yuzu is not directly related to C. ichangensis but to an unknown Papeda that does probably not exist any more, which is at least not known today to any citrus expert. I try to remember the article. It was not on Yuzu but on the genetic relationship of Citrus in general. Perhaps I remember. Then I can post it here.

Ilya11

  • Hero Member
  • *****
  • Posts: 752
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: Yuzu Ichang Papeda cross
« Reply #26 on: December 09, 2020, 05:19:30 PM »
Here it is: link
Best regards,
                       Ilya

SoCal2warm

  • Hero Member
  • *****
  • Posts: 1391
    • zone 10 and zone 8a
    • View Profile
Re: Yuzu Ichang Papeda cross
« Reply #27 on: December 10, 2020, 04:31:06 AM »
You read it everywhere that Yuzu is a hybrid of Ichang Papeda. But genetic studies are not in favor of that constantly repeated supposition.
It is not known for certain how Yuzu originated, but genetic studies do confirm that Yuzu is closely related to Ichang papeda; it is just not known with certainty exactly how.

It's not even really known/agreed whether Yuzu should constitute its own species or came about as the result of hybridization.
There are some records from ancient times of citrus grown fairly far north near the Yangtze river, where citrus does not normally grow, but due to the ambiguities in the Chinese language, we cannot be sure exactly what type of modern variety those fruits would correlate to. They might not have had separate words for the two.

One possibility, sometimes separate species can evolve with genetic introgression from another species. This basically means there's a genetic pool of many separate individuals, and gradually over time, genes from an outside species enter into that gene pool, through many separate individual hybridization events, over many generations.

I don't want to get too much into this topic here, however.

Till

  • Member
  • ***
  • Posts: 34
    • Germany, Simmerath (City), Zone 6b
    • View Profile
Re: Yuzu Ichang Papeda cross
« Reply #28 on: December 10, 2020, 05:25:47 AM »
Thank you, Ilya. For those who do not want to read too much, just look for the headline "Origins of C. ichangensis and other acid citrus varieties" in the article. Interesting also what it states about Ichang Lemon.

If someone wants to create new hybrids the exact genetic relationships of different species can often be ignored when you just look at the results of antient hybridization events and take them as they are. I think, however, that such a practical and somewhat superficial approach should keep us away from too much speculation. The motto "just try!" is good, often perhaps the only think we can do. But we should then not be disappointed when we don't get what we wanted if our plans and wishes were based on wrong assumptions about the nature of the parent species we used.

SoCal2warm

  • Hero Member
  • *****
  • Posts: 1391
    • zone 10 and zone 8a
    • View Profile
Re: Yuzu Ichang Papeda cross
« Reply #29 on: December 10, 2020, 07:50:22 PM »
I am content to regard Yuzu as most likely having arisen from hybridization between Ichang papeda and sour mandarin or mandarin, probably not from a single hybridization event.

There may have been a cross between the two, and after that the offspring got propagated from seed, so there was further genetic mix-up.
In the initial cross, Ichang papeda probably would have been the female parent. The genetic marker studies show that Yuzu shares a much closer affinity to Ichang papeda than to mandarin.

"Sour mandarin" may be a sub-species of mandarin, kind of like a wild mandarin type, originally native to China.
Or it may be possible "sour mandarin" actually came from the regular species of mandarin but just with a little bit of Ichang papeda-type genes mixed in.

(If you look at the Hybrid Origins of Citrus Varieties Inferred from DNA Marker Analysis of Nuclear and Organelle Genomes, Tokurou Shimizu, article, Citrus sunki seems to stand out as the only near pure mandarin with some additional few genes like C. ichangensis or C. medica, probably the former)

If that is the case, then it may be of little meaning whether the ancestry came from sour mandarin or mandarin. And it is also of course a possibility sour mandarin may have ultimately arisen from Yuzu, rather than the other way around. Or even no direct parental relationship.

None of this is fact, it is informed speculation, an attempt to try to fit together the pieces.

We don't know if this hybridization resulted naturally, or came about as a result of human activity.

I will quote a source here:

" Swingle and Reece (1967) noted that: [] hybrids that show astonishing similarity to the Yuzu have now been produced in this country between the Ichang papeda and the satsuma orange (a form of C. reticulata ). "

https://idtools.org/id/citrus/citrusid/factsheet.php?name=Yuzu

Which lends some support to the hybridization theory.

 

Copyright © Tropical Fruit Forum - International Tropical Fruit Growers