Tropical Fruit Forum - International Tropical Fruit Growers



Author Topic: keraji mandarin  (Read 3435 times)

SoCal2warm

  • Sr. Member
  • ****
  • Posts: 446
    • zone 10 and zone 8a
    • View Profile
keraji mandarin
« on: December 20, 2017, 07:35:50 PM »
Keraji is a cold hardy Japanese mandarin with yellow-orange skin. The taste is like lemonade and the fruits are small and a bit seedy. Supposedly keraji can handle down to 12 °F.

One tree was growing outside unprotected and fruiting in Virginia Beach.

Apparently it was a fairly popular tree in the Southeast among those growing cold hardy citrus, but I can't seem to find any nurseries carrying it now.

A nursery owner in Georgia was kind enough to send me seeds


During my research I came across something interesting in a Japanese genetic analysis paper. Seems like keraji shares in common a parent with satsuma mandarin, a type of Japanese tangor called kunenbo which must be confering a degree of exceptional cold hardiness (it's a parent of bloomsweet as well). The analysis actually indicated keraji was probably a backcross of kunenbo with another sour-type citrus known as kubachi (today rather obscure, but the pictures I was able to find look similar to kabosu or sudachi).

I just read another research paper DNA analysis that says keraji appears to be a cross between kunenbo (seed parent) and kikai-mikan. I found a picture of kikai-mikan and not surprisingly the fruit looks a lot like a cross between both the pictures of kubachi and kunenbo I saw. So it looks like keraji may indeed be a backcross with kunenbo—that is (kubachi x kunenbo) x kunenbo.

For any of you who may be interested, here's the picture of kikaimikan (喜界みかん) I was able to find:


And here's here's a Japanese site showing pictures and description of Kunenbo:
http://www.michinosima.com/kaimono/kunenbo.html

The name Kunenbo translates as "nine year mother". The fruits appear pretty similar to a Kara mandarin. (One of Kara's parents is Satsuma, and Satsuma is a Kunenbo cross with Kishu. Kara is also pretty cold hardy and grows in frosty areas of Japan. Maybe that's giving too much information here)

I suspect there might be different cultivars of keraji as well, with slightly different qualities when it comes to edibility/flavor, if these plants have been propagated at some point from seed. The seeds seemed pretty big like they would be really easy to grow, so that may be likely.

Well that's pretty funny, I start a thread about keraji and show you pictures of its entire lineage of obscure parents but don't show you a picture of keraji itself. Well, there are plenty of pictures of keraji mandarin on the internet so you don't need me to post that there.













AndrewAZ

  • Member
  • ***
  • Posts: 119
    • Scottsdale, AZ zone 9b
    • View Profile
Re: keraji mandarin
« Reply #1 on: December 20, 2017, 11:08:15 PM »
Does anyone else have keraji seeds to share?  I love the fruit.  Willing to pay or trade.

Walt

  • Member
  • ***
  • Posts: 59
    • USA, Kansas, Kanopolis, zone 6
    • View Profile
Re: keraji mandarin
« Reply #2 on: December 21, 2017, 12:59:06 PM »
Looks like I'll be getting  keraji  too.

SoCal2warm

  • Sr. Member
  • ****
  • Posts: 446
    • zone 10 and zone 8a
    • View Profile
Re: keraji mandarin
« Reply #3 on: December 21, 2017, 02:30:24 PM »
Looks like I'll be getting  keraji  too.
I'm not sure why you'd want to have keraji. It's not going to be able to survive outside in Kansas, zone 6. And the fruit quality is not going to be anywhere as good as regular mandarins.
Keraji might be of more interest to someone in climate zone 8a.

I know you're planning to use it in your hybridization attempts, but in zone 6 you may be better off just breeding trifoliate with regular citrus. Keraji doesn't have anywhere near the same cold hardiness as a citrange, for example. I think you wouldn't be bad off just using Satsuma mandarin in your hybridization instead.

Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #4 on: December 22, 2017, 04:10:16 AM »
Keraji is more cold resistant than Morton citrange.
Best regards,
                       Ilya

Sylvain

  • Member
  • ***
  • Posts: 92
    • Bergerac, France
    • View Profile
    • Looking for Wakonai.
Re: keraji mandarin
« Reply #5 on: December 23, 2017, 05:04:58 AM »
> From what I know precocious flowering gene in poncirus is recessive
> I agree with you about those recessive genes, Walt.
I received them as seeds and all the seedling flowered  one and half year later.
But it doesn't prove it is not recessive because all the seeds could be nucellare.

Walt

  • Member
  • ***
  • Posts: 59
    • USA, Kansas, Kanopolis, zone 6
    • View Profile
Re: keraji mandarin
« Reply #6 on: January 02, 2018, 02:18:29 PM »
While I am using citranges and citandarins in my breeding  Even they must be inside during my winters.  Having some mandarins inside to keep me company during the winter is not a problem.  None of my citranges are from modern breeding.  Having the most hardy mandarines in my breeding populations seems a good idea to me.
Crossing the most cold-hardy mandarins available with the rather new, new to me at least, better flavored P. trifoliata is worth doing.

SoCal2warm

  • Sr. Member
  • ****
  • Posts: 446
    • zone 10 and zone 8a
    • View Profile
Re: keraji mandarin
« Reply #7 on: March 15, 2018, 06:53:51 PM »
just an update, it looks like keraji seeds are being sold on Amazon
https://www.amazon.com/Citrus-reticulata-KERAJI-MANDARIN-Hardy/dp/B01DA7A464

I just planted two of my keraji seedlings into the ground:



They grew from seed fast since they were under optimal growing conditions.
« Last Edit: March 15, 2018, 07:02:12 PM by SoCal2warm »

Moro

  • Newbie
  • *
  • Posts: 8
    • Switzerland, Lake of Constance, 7b/8a
    • View Profile
Re: keraji mandarin
« Reply #8 on: March 16, 2018, 07:02:33 AM »
I have a Keraji planted outside at a spot close to the greenhouse wall and protected against the Eastern winds that bring the cold snaps of air from Russia.

We had a mild winter in December and January followed by a brutally cold week in late February with two nights at -11C (12F) and highs during the day at -6C (21F). The tree survived without damages except a few lost leaves. I wrapped it in frost cloth during the coldest nights.

My Ichangquat has no protection against the wind from the East and lost more leaves than the Keraji but still no big damages.

Both were planted in 2016 and are about 1.2m (4 ft) tall.

Zitrusgaertner

  • Member
  • ***
  • Posts: 61
    • Vienna, Austria, European Union 7b
    • View Profile
    • www.agrumi.at
Re: keraji mandarin
« Reply #9 on: March 16, 2018, 09:18:57 AM »
Moro, my Ichangquat has a quite big crack in its bark right above the craft union. The Ichangquat is the only one of my outdoor-citri that is not high-crafted.

maesy

  • Member
  • ***
  • Posts: 23
    • Lucerne, Switzerland
    • View Profile
Re: keraji mandarin
« Reply #10 on: March 18, 2018, 07:33:08 AM »
My ichangquat is planted out at the good protected south eastern wall of my house. It took similar temperatures as yours moro. It is untouched and looks in perfect condition.
I guess it is not much less hardy as a dunstan citrumelo
Three meters beside and away of the house.

Can anybody say something to the fruit quality of ichangquat?
Mine is from eisenhut, not 6-7-2.

According the keraji, I have one growing well protected growing together with a thomasville citrangequat at the south western wall of my house.


Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #11 on: March 18, 2018, 08:33:56 AM »
It is highly probable ;) that ichangquat from Eisenhut is the same that is sold by B.Voss by the name 6-7-2.
Mine 6-7-2 is a huge tree around 6 meters tall, never protected and never had any damage (planted in 2004).
It is flowering in several waves all summer long, fruits are ripening very quickly, in around 3-4 months. The fruit quality is variable, depends on weather and  degree of ripeness. It is best to be picked when easily detached from  the branch. 
A flavor is unique, some melange of pine with feijoa; not unpleasant, with small grapefruit-like bitterness.
Occasionally fruits are rather dry inside, but mostly the juice is present in sufficient quantity.
I like to eat them as such, but they also  can be used for marmalade.




Concerning Keraji, no protection, no damage this winter as well as the last one.
Best regards,
                       Ilya

maesy

  • Member
  • ***
  • Posts: 23
    • Lucerne, Switzerland
    • View Profile
Re: keraji mandarin
« Reply #12 on: March 18, 2018, 09:36:50 AM »
Here is a picture of mine. It is very thorny. Do you think it could be the same as yours?


I'm going to plant it at another place where there is more room for it to grow.
In its place I will plant a ichangensis x sinensis which seems to be less hardy and probably remains at a smaller size.


Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #13 on: March 18, 2018, 10:06:55 AM »
The leaves look the same. When young the thorns were also present on small branches, now they are  mostly on the trunk.
My plant was from B.Voss, immature wood grafted on poncirus, first flowering was in 2008.
Best regards,
                       Ilya

maesy

  • Member
  • ***
  • Posts: 23
    • Lucerne, Switzerland
    • View Profile
Re: keraji mandarin
« Reply #14 on: March 18, 2018, 11:28:39 AM »
Thank you Ilya.

Btw, what was your lowest temperature? And do you also get prolonged frost?

Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #15 on: March 18, 2018, 01:23:07 PM »
-9C at the end of February with a strong NE wind reaching 75km/h

Best regards,
                       Ilya

Florian

  • Member
  • ***
  • Posts: 96
    • Solothurn, Switzerland.
    • View Profile
Re: keraji mandarin
« Reply #16 on: March 19, 2018, 08:28:37 AM »
For what it's worth, Eisenhut lists two cultivars, the 6-7-2 and another one (their number 245). They told me it is a sister seedling and has not yet fruited.

Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #17 on: March 19, 2018, 09:29:51 AM »
Since original (USDA Florida) 6-7-2 is monoembryonic, its European seedlings  should be different from mother plant.
Contrary to the original description, my  "6-7-2" of B.Voss gives very small number of seeds (1 per ~10 fruits).
1/3 of them contain green embryos, the rest are white.
Best regards,
                       Ilya

maesy

  • Member
  • ***
  • Posts: 23
    • Lucerne, Switzerland
    • View Profile
Re: keraji mandarin
« Reply #18 on: March 19, 2018, 10:53:40 AM »
As I remember mine is not 6-7-2, it's the other one with number 245, since 6-7-2 was not available.

Moro

  • Newbie
  • *
  • Posts: 8
    • Switzerland, Lake of Constance, 7b/8a
    • View Profile
Re: keraji mandarin
« Reply #19 on: March 20, 2018, 04:59:39 AM »
I have the 245. It had the first two flowers late last autumn, i.e. no fruits because of the start of winter. Don't know whether it will be able to flower this spring after the arctic conditions in February and March.

Zitrusgaertner

  • Member
  • ***
  • Posts: 61
    • Vienna, Austria, European Union 7b
    • View Profile
    • www.agrumi.at
Re: keraji mandarin
« Reply #20 on: March 20, 2018, 05:21:54 AM »
Moro, to which register does "245" refer? USDA-List? Is your plant in opern ground? Or is it potted?

Best Regards Robert

Florian

  • Member
  • ***
  • Posts: 96
    • Solothurn, Switzerland.
    • View Profile
Re: keraji mandarin
« Reply #21 on: March 20, 2018, 08:06:14 AM »
The 245 in Eisenhut's list, the 6-7-2 is their 244.

Moro

  • Newbie
  • *
  • Posts: 8
    • Switzerland, Lake of Constance, 7b/8a
    • View Profile
Re: keraji mandarin
« Reply #22 on: March 20, 2018, 09:01:20 AM »

Radoslav

  • Hero Member
  • *****
  • Posts: 581
    • Slovakia
    • View Profile
Re: keraji mandarin
« Reply #23 on: March 20, 2018, 12:43:43 PM »
Keraji is a cold hardy Japanese mandarin with yellow-orange skin. The taste is like lemonade and the fruits are small and a bit seedy. Supposedly keraji can handle down to 12 °F.

One tree was growing outside unprotected and fruiting in Virginia Beach.

Apparently it was a fairly popular tree in the Southeast among those growing cold hardy citrus, but I can't seem to find any nurseries carrying it now.

A nursery owner in Georgia was kind enough to send me seeds


During my research I came across something interesting in a Japanese genetic analysis paper. Seems like keraji shares in common a parent with satsuma mandarin, a type of Japanese tangor called kunenbo which must be confering a degree of exceptional cold hardiness (it's a parent of bloomsweet as well). The analysis actually indicated keraji was probably a backcross of kunenbo with another sour-type citrus known as kubachi (today rather obscure, but the pictures I was able to find look similar to kabosu or sudachi).

I just read another research paper DNA analysis that says keraji appears to be a cross between kunenbo (seed parent) and kikai-mikan. I found a picture of kikai-mikan and not surprisingly the fruit looks a lot like a cross between both the pictures of kubachi and kunenbo I saw. So it looks like keraji may indeed be a backcross with kunenbo—that is (kubachi x kunenbo) x kunenbo.

For any of you who may be interested, here's the picture of kikaimikan (喜界みかん) I was able to find:


And here's here's a Japanese site showing pictures and description of Kunenbo:
http://www.michinosima.com/kaimono/kunenbo.html

The name Kunenbo translates as "nine year mother". The fruits appear pretty similar to a Kara mandarin. (One of Kara's parents is Satsuma, and Satsuma is a Kunenbo cross with Kishu. Kara is also pretty cold hardy and grows in frosty areas of Japan. Maybe that's giving too much information here)

I suspect there might be different cultivars of keraji as well, with slightly different qualities when it comes to edibility/flavor, if these plants have been propagated at some point from seed. The seeds seemed pretty big like they would be really easy to grow, so that may be likely.

Well that's pretty funny, I start a thread about keraji and show you pictures of its entire lineage of obscure parents but don't show you a picture of keraji itself. Well, there are plenty of pictures of keraji mandarin on the internet so you don't need me to post that there.


What is kubachi? I know Kābuchi カーブチ , which is the name for citrus keraji.

SoCal2warm

  • Sr. Member
  • ****
  • Posts: 446
    • zone 10 and zone 8a
    • View Profile
Re: keraji mandarin
« Reply #24 on: March 20, 2018, 07:17:01 PM »
What is kubachi?
Apparently a rare obscure citrus that is very specific to a particular region in Japan.

I don't think we know how it originated, though I would guess it's likely descended from either Yuzu or C. taiwanica.
All I can tell you is that I was able to find a picture of it on a Japanese site, and it looked very similar to Sudachi and Kabosu (which I'm pretty both originated from hybrid pollination from yuzu).
I know Sudachi is pretty cold hardy (maybe not quite as hardy as Yuzu). I read on another site someone was managing to grow it outside near Portland, OR.
Yuzu, Sudachi, Kabosu, they were all used in a similar way to lemons in traditional Japanese cuisine.
« Last Edit: March 20, 2018, 07:22:16 PM by SoCal2warm »

Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #25 on: March 21, 2018, 05:12:17 AM »
In this paper of DNA analysis the spelling is kabuchi ,not kubachi
Best regards,
                       Ilya

Radoslav

  • Hero Member
  • *****
  • Posts: 581
    • Slovakia
    • View Profile
Re: keraji mandarin
« Reply #26 on: March 21, 2018, 12:34:52 PM »
Kābuchi  (C. keraji hort. ex Tanaka var. kabuchii hort. ex Tanaka) カーブチ (かーぶちー)
is common citrus.


Ilya11

  • Sr. Member
  • ****
  • Posts: 273
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: keraji mandarin
« Reply #27 on: March 21, 2018, 01:23:09 PM »
In the same DNA marker  paper it is shown that Kabuchi and Unzoki are hybrids of Kunenbo-A  and unknown citrus with cytoplasm coming from sweet orange, while Keraji is a back cross of Kabuchi to Kunenbo-A
Best regards,
                       Ilya

Radoslav

  • Hero Member
  • *****
  • Posts: 581
    • Slovakia
    • View Profile
Re: keraji mandarin
« Reply #28 on: March 21, 2018, 01:59:13 PM »
In the same DNA marker  paper it is shown that Kabuchi and Unzoki are hybrids of Kunenbo-A  and unknown citrus with cytoplasm coming from sweet orange, while Keraji is a back cross of Kabuchi to Kunenbo-A

In one DNA study I read, that kabuchi is kunenbo x citrus  yatsushiro in another kunenbo x something like citrus depressa.
Kabuchi is chance seedling from Okinawa.

SoCal2warm

  • Sr. Member
  • ****
  • Posts: 446
    • zone 10 and zone 8a
    • View Profile
Re: keraji mandarin
« Reply #29 on: March 21, 2018, 04:39:23 PM »
In this paper of DNA analysis the spelling is kabuchi ,not kubachi
My apologies, it is indeed spelled kabuchi.


In one DNA study I read, that kabuchi is kunenbo x citrus  yatsushiro in another kunenbo x something like citrus depressa.
Kabuchi is chance seedling from Okinawa.
That would be interesting, so it appears keraji is a triple backcross of kunenbo with some other original citrus. Probably some sour citrus I am guessing, maybe Yuzu.

Kunenbo appears to be some sort of mandarin x tangelo hybrid, or something like it, analogous to the type of citrus known as a tangor (Temple orange and Page mandarin could also fall into this category). What I mean is that kunenbo probably has a buntan (pomelo) ancestor going back two or three generations. That would explain its fragrance. Whether it also may have some other cold hardy species in its ancestry (like Yuzu) I'm not sure. I will point out that it doesn't necessarily have to have been descended from a cold hardy species to develop a fairly high degree of cold tolerance over several generations. The central coastal region of Japan can get quite cold some Winters, every 25 years or so. That could have killed off the less hardy citrus. From there it would be natural selection as the citrus gradually started making its way up North, over successive generations. This would also leave me inclined to think that kunenbo is probably at least in substantial part zygotic, although I don't have any information on that.
« Last Edit: March 21, 2018, 05:00:51 PM by SoCal2warm »

jim VH

  • Member
  • ***
  • Posts: 10
    • Vancouver,Wa. zone 8b
    • View Profile
Re: keraji mandarin
« Reply #30 on: March 22, 2018, 10:58:37 AM »


I know Sudachi is pretty cold hardy (maybe not quite as hardy as Yuzu). I read on another site someone was managing to grow it outside near Portland, OR.


Yes, My Sudachi and Yuzu easily survived 8F (-13.3C) in January 2017 in Vancouver Wa., just across the Columbia river from Portland Or., with only minor small twig damage and about 20% defoliation on each.  The Sudachi appeared to have a higher percentage of small twig damage than the Yuzu.  On the other hand, the Yuzu is a much larger tree, and size does matter.

SoCal2warm

  • Sr. Member
  • ****
  • Posts: 446
    • zone 10 and zone 8a
    • View Profile
Re: keraji mandarin
« Reply #31 on: May 16, 2018, 05:47:30 PM »
here's a keraji seedling



maesy

  • Member
  • ***
  • Posts: 23
    • Lucerne, Switzerland
    • View Profile
Re: keraji mandarin
« Reply #32 on: May 18, 2018, 06:38:25 AM »
My keraji together with thomasville



 

Copyright © Tropical Fruit Forum - International Tropical Fruit Growers