Tropical Fruit Forum - International Tropical Fruit Growers

Citrus => Cold Hardy Citrus => Topic started by: Florian on April 15, 2017, 07:43:56 PM

Title: Citsuma Prague
Post by: Florian on April 15, 2017, 07:43:56 PM
I'd like to share a picture of my Citsuma Prague which is the most bizarre citrus I have.
It has grown pretty well but it seems it wants to grow in all directions but upwards. If I let it grow it would be much wider than tall.
I know Ilya has one, too. I'd love to see some pictures.

(https://s14.postimg.cc/a5fdqbkh9/IMG_3696.jpg) (https://postimg.cc/image/a5fdqbkh9/)
Title: Re: Citsuma Prague
Post by: Citradia on April 15, 2017, 10:12:11 PM
That's neat. I wish I had a citsuma Prague. Would be nice to have a tree from , as grandma says, " the old country". The growth habit looks a lot like my citrange seedlings.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 16, 2017, 02:32:37 PM
You have very nice specimen. I have this Citsuma in the ground since 2004, but it is grafted on very weak rootstock and has not grown much. Never damaged, but flowering is very sporadic and fruits rapidly abort.
(http://s019.radikal.ru/i629/1704/8b/c69ad9d711f2.jpg) (http://radikal.ru)

Last year I regrafted it on high stem of very strong poncirus, hope it will finally give some fruits.
Sylvain in Dordogne have very nice plant, almost 2 meters high , producing sweet fruits of very good quality.
Title: Re: Citsuma Prague
Post by: Millet on April 16, 2017, 03:10:45 PM
Ilya,11 the Satsuma Prague is a cross between the Citsuma unshiu X Poncirus trifoliata correct?
Title: Re: Citsuma Prague
Post by: Ilya11 on April 16, 2017, 04:10:30 PM
Millet,
Its origin is not yet clear. Leaves are  a mixture of bi- tri- or monofoliates.
The fruits are almost satsuma like, no poncirus smell or taste.
There is    suspicion that it is a chimera between poncirus and satsuma, but strangely enough even stems and leaves do not have odor or taste of poncirus.
Scientists in Brno show that the nuclei from its cells have homogeneous DNA content, that does not definitely  proves an absence of chimerism , but points more to the hybrid origin of this citrus.
On the other hand, Roberto from Wien observed an emergence of  poncirus like branch   distantly  from   grafting point.
It could be some second generation poncirus-satsuma hybrid with unstable genome, but no definite proof for this exists for the moment.
Title: Re: Citsuma Prague
Post by: Millet on April 16, 2017, 08:48:05 PM
Interesting, to bad there is no supplier of the tree in the USA.
Title: Re: Citsuma Prague
Post by: Florian on April 17, 2017, 06:25:21 AM
Thank you so much for the information, Ilya. My plant is a strong grower but I would still like to graft it onto a taller poncirus because I like tree forms better. I will let it grow until it flowers and try to graft it then. I need more time anyway because my poncirus rootstocks are still very small since I have to grown them from seed.
Title: Re: Citsuma Prague
Post by: Radoslav on April 17, 2017, 09:12:07 AM
Interesting, to bad there is no supplier of the tree in the USA.

I have a strong feeling, that mrtexas showed at old forum (few years ago) plant, which most likely is Citsuma Prague and he propagated it as great satsuma like mandarin with great hardiness.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 17, 2017, 01:06:32 PM
It could be this variety in UCR collection:
http://www.citrusvariety.ucr.edu/citrus/citrondarin.html (http://www.citrusvariety.ucr.edu/citrus/citrondarin.html)

(http://www.citrusvariety.ucr.edu/citrus/images/CitrondarintrifoliatexsatsumahybridCRC3881006.jpg)
Title: Re: Citsuma Prague
Post by: Millet on April 17, 2017, 03:54:22 PM
ILYA11 Thanks for the link
Title: Re: Citsuma Prague
Post by: Citradia on April 17, 2017, 06:33:32 PM
I looked up chimera and looks like it is two different species fused together. Do we call this citrandarin chimera instead of hybrid because it has a good mandarin quality fruit on a trifoliata tree, whearas most trifoliate hybrids have a tree body and fruit that is a mix or blending of the two parent trees?
Title: Re: Citsuma Prague
Post by: Florian on April 18, 2017, 02:33:07 AM
Well, Ilya said that the homogenous dna makes it rather unlikely to be a chimera but I am no expert.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 18, 2017, 04:21:25 AM
It is believed for a long time to be a chimera, but its origin is very obscure.
It is either originated in Abkhazia region of the USSR or  in  Prague, Czechoslovakia.
In USSR several attempts were made to produce poncirus/citrus chimera by the induction  and subsequent regeneration of massive callus at the grafting point.
By this, they believed to produce  plants containing cells from two species (chimeras). Most of such plants are unstable, giving branches of pure species, but occasionally a stable, so called periclinal chimera can be produced.
In the recent study   Czech scientists  isolated the cell nuclei from this plant, stained their genetic material (DNA) by fluorescent die and determined the intensity of fluorescence signal from individual nuclei. Since the genome of different citruses is slightly different in size, they hopped to see two peaks of fluorescent intensity if it is satsuma/poncirus chimera.
They observed only one, so it is either not a chimera  but a hybrid or   chimera  between poncirus  with some hybrid having approximately the  same  genome size as poncirus.
I guess only molecular markers can definitely  resolve the origin of this very strange plant.
Title: Re: Citsuma Prague
Post by: Radoslav on April 18, 2017, 04:48:44 AM
According to Snek, there are three hybrids/chimeras known in former Czechoslovakia.
One is hybrid Unshiu x Poncirus selected by professor Pospisil in seventies, the plant is still in greenhouse of university in Prague.
(https://s10.postimg.cc/ur8uq26l1/Ushiu_Prague.jpg) (https://postimg.cc/image/ur8uq26l1/)
(from the book „Pěstování citrusů“, c. SZN 1987, Ing. Stanislav Hušák, CSc., Doc.Ing. Vladimír Táborský, CSc., Prof. Ing. Pavel Valíček, DrSc.)
Second one is Chimere no.19 (unshiu  poncirus) from USSR.
(https://s11.postimg.cc/v6v3sl3f3/Chimera_No19_Unshiu_PT.jpg) (https://postimg.cc/image/v6v3sl3f3/))
(from the book „Pěstování citrusů“, c. SZN 1987, Ing. Stanislav Hušák, CSc., Doc.Ing. Vladimír Táborský, CSc., Prof. Ing. Pavel Valíček, DrSc.
And third one: hybrid P.t. X Unshiu from USSR too.



Title: Re: Citsuma Prague
Post by: Ilya11 on April 18, 2017, 07:48:01 AM
According to Snek, there are three hybrids/chimeras known in former Czechoslovakia.
One is hybrid Unshiu x Poncirus selected by professor Pospisil in seventies, the plant is still in greenhouse of university in Prague.
Radoslav,
Have you seen the recent photos of this surviving plant?
For me the old black and white picture of it looks very similiar to what I have in the garden.
On other hand, the picture from Riverside is also similiar, although their plant is described as chimera from Abkhazia.
Title: Re: Citsuma Prague
Post by: Sylvain on April 20, 2017, 07:32:13 AM
Quote
It has grown pretty well but it seems it wants to grow in all directions but upwards.
After few years the shoots go strait to the sky.

Quote
Sylvain in Dordogne have very nice plant, almost 2 meters high , producing sweet fruits of very good quality.
The tallest is now 2.50m. The second one is about 2m high and last year I made a third that is a little less than 2m. The last one is an over-graft on a '5 stars' grafted on PT. It is very vigorous.

Quote
Leaves are  a mixture of bi- tri- or monofoliates.
Like shown on the Ilya11's picture bifoliate and trifoliates are very rare. Most are deformed monofoliates.

Quote
The fruits are almost satsuma like
Not 'almost', they are pure satsuma fruits.

Quote
There is suspicion that it is a chimera between poncirus and satsuma
For me there is no doubt, it is a chimera.
This spring one very big flower appeared just at the same time than the poncirus flowers. Looking exactly the same. The Prague chimeras bloom nearly one month later with small flowers. The fruitlet issued from this flower is already big and have a velvet skin.
Now we know that the poncirus that made the chimera is of the large flowers kind.
Last year I had one seed from the fruits (the first one). It gave three seedlings that are pure mandarins.

Quote
It could be this variety in UCR collection
I don't think so. The fruits are very different. This one looks more like an orange than like a mandarin.



Title: Re: Citsuma Prague
Post by: Ilya11 on April 20, 2017, 09:10:31 AM
Sylvain,
Have you been able to germinate its seeds?
Title: Re: Citsuma Prague
Post by: Sylvain on April 21, 2017, 04:50:43 AM
Yes, I have three seedlings growing.
Title: Re: Citsuma Prague
Post by: Florian on April 21, 2017, 05:09:35 AM
Sylvain, would you have a picture of your plant and fruit?
Title: Re: Citsuma Prague
Post by: Ilya11 on April 21, 2017, 08:16:28 AM
Yes, I have three seedlings growing.
Is it possible to see them, please?
Title: Re: Citsuma Prague
Post by: Sylvain on April 21, 2017, 06:24:15 PM
I came back home late and the light isn't good. :(

The tree:
(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/prague.png)

Growing strait toward the sky:
(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/croissance2.png)

(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/croissance.png)

Velvet fruit:
(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/pt.png)

Regular fruit:
(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/fruit.png)

The first years the flowers were very small and irregular, with the time the flowers stabilize with three petals:
(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/fleurs.png)

The seedlings:
(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/semis1.png)

(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Prague2/semis2.png)

Does someone dare to say it is not a chimera?
Title: Re: Citsuma Prague
Post by: Millet on April 21, 2017, 08:22:16 PM
Silvain it is sure easy to see the Poncirus parentage in your tree.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 22, 2017, 03:38:36 AM
Thank you Sylvain,
Your tree is huge and magnificent.
From what you presented it is clear it is a chimera between poncirus and pure satsuma.
Where you did got the budwood from?
Title: Re: Citsuma Prague
Post by: Sylvain on April 22, 2017, 07:01:34 AM
It was from Petr Broza. At this time (2008/2009) we were only three (with B. Voss who found it) to have it.
Title: Re: Citsuma Prague
Post by: Radoslav on April 22, 2017, 11:10:36 AM
Ąll what i know about this case, is that  snek thinks, that Voss during his visit in greenhouse in university of Prague dig out and took with him plant that was not the plant snek calls hybrid Unshiu x Poncirus, selected by professor Pospisil, but Chimere no.19 (unshiu  poncirus) from USSR. Voss gave it name citsuma Prague, but it is not the citsuma Prague which for example Snek and some others have in their collections. Chimere no.19 , grows upright, while  so called hybrid grows more like flying dragon, or willow.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 22, 2017, 11:46:44 AM
Radoslav,
I got my plant from B.Voss in 2004 and it looks exactly like a plant that has  Snek ( willow like with slim contorted  twigs).   
Title: Re: Citsuma Prague
Post by: Radoslav on April 22, 2017, 01:36:22 PM
i have never been interested in so called hardy citruses, but in this case I am forced  ;D to start a little investigation  8). Last week I personally met with one of the founders of czechoslovakian citrus growing. He grows citruses for more than 65 years. He traveled across USSR many times serching for citruses and other agricultural plants. He personally grafted some budwood on The Friendship Tree in Sochi, he speaks fluently russian, ukrainian, chechen, georgian etc. He cooperated with all soviet citrus experimental stations. Yesterday I sent him an e-mail and asked him about this case, because he cooperated with professor Pospisil in seventies. Once he will answer my question, I let you know more.
Title: Re: Citsuma Prague
Post by: Millet on April 22, 2017, 03:40:55 PM
For members that do not know what the Citrus Friendship Tree is that Radoslav wrote about in the above post see link below:

https://en.wikipedia.org/wiki/Friendship_Tree
Title: Re: Citsuma Prague
Post by: Sylvain on April 22, 2017, 07:23:03 PM
Radoslav, the one we have is not the Chimere no.19. On our plants the leaves are smaller than the fruits and the fruits are spherical not depressed at the apex.
And yes, it looks like flying dragon. For years mine behaved like this. It is only since two years that it started to grow upright.
Voss, Brosa, Snek, Ilya and I have the same plant. On the pictures there is no doubt.

Could you take a picture of the one witch still remains in the greenhouse in university of Prague? This way I could tell you if it's the same plant than the one we have.
Title: Re: Citsuma Prague
Post by: Radoslav on April 24, 2017, 04:35:46 AM
I asked for picture, once I receive it, I will post it.
Title: Re: Citsuma Prague
Post by: Florian on April 26, 2017, 04:15:06 AM
This topic is turning out to be so great, thank you all for your contributions.
Sylvain, your plant has a nice, tall trunk. Did it form that all by itself or did you prune it that way? I am asking because you say it will grow upwards over time anyway but at the moment I doubt a bit that mine would form such a nice trunk..
Title: Re: Citsuma Prague
Post by: Radoslav on April 26, 2017, 01:44:38 PM
Just one note to the topic. Professor Pavel Valíček, co author of the book Pěstování citrusů (Growing of citruses) issued in 1987 from which are the pictures, confirmed to me, that hybrid Unshiu x Poncirus was selected by professor Pospisil in seventies, the plant is still in greenhouse of university in Prague.
But I remember that Ilya posted at old forum article, that unshiu mandarins do not hybridize and cross pollination with poncirus is only used to obtain seeds to get nucellar seedlings, or mutants. So it is possible that plant mentioned above is chimera, or mutant.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 26, 2017, 03:34:31 PM
But I remember that Ilya posted at old forum article, that unshiu mandarins do not hybridize and cross pollination with poncirus is only used to obtain seeds to get nucellar seedlings, or mutants. So it is possible that plant mentioned above is chimera, or mutant.
It is not a case, pollination with foreign pollen is used to enhance seed  formation in satsuma.
Poncirus is used because  its hybrids with satsuma having three leaflets are easily distinguished from   nucellar seedlings that are screened for for new traits emerging through natural somatic mutagenesis.
Title: Re: Citsuma Prague
Post by: Millet on April 27, 2017, 11:54:20 AM
The odds of a mutant must be every slim, taking many many many  seed germinations.
Title: Re: Citsuma Prague
Post by: Ilya11 on April 27, 2017, 01:25:52 PM
Of course, you need a large population of nucellar seedlings to produce better varieties.
But somatic mutations are not particularly rare.  Out of 200 nucellar seedlings  of Miyagawa-wase two new varieties: 'Okitsu-Wase' and 'Miho-Wase were selected in Japan.
http://fshs.org/proceedings-o/1964-vol-77/79-83%20(NISHIURA).pdf (http://fshs.org/proceedings-o/1964-vol-77/79-83%20(NISHIURA).pdf)
also (https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwiRvd3Cj8XTAhWBcBoKHVX1CG0QFggyMAE&url=https%3A%2F%2Fwww.jircas.go.jp%2Fja%2Ffile%2F7021%2Fdownload%3Ftoken%3Dlp9TJOTV&usg=AFQjCNH24UhPapPBEfwwHa6s_7bi6tqMdA&cad=rja)
Title: Re: Citsuma Prague
Post by: Millet on April 27, 2017, 03:41:09 PM
Plus not all mutations are superior varieties, some mutations are inferior varieties. Even then it could take 5- 10 years before fruit developed to determine if the new mutant is worth while. However it is always an adventure. Good luck.
Title: Re: Citsuma Prague
Post by: Sylvain on April 27, 2017, 06:54:13 PM
> Sylvain, your plant has a nice, tall trunk. Did it form that all by itself or did you prune it that way?
It is the rootstock (poncirus).
Title: Re: Citsuma Prague
Post by: Radoslav on April 28, 2017, 07:50:15 AM
Of course, you need a large population of nucellar seedlings to produce better varieties.
But somatic mutations are not particularly rare.  Out of 200 nucellar seedlings  of Miyagawa-wase two new varieties: 'Okitsu-Wase' and 'Miho-Wase were selected in Japan.
[url]http://fshs.org/proceedings-o/1964-vol-77/79-83%20(NISHIURA).pdf[/url] ([url]http://fshs.org/proceedings-o/1964-vol-77/79-83%20(NISHIURA).pdf)[/url]
also ([url]https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwiRvd3Cj8XTAhWBcBoKHVX1CG0QFggyMAE&url=https%3A%2F%2Fwww.jircas.go.jp%2Fja%2Ffile%2F7021%2Fdownload%3Ftoken%3Dlp9TJOTV&usg=AFQjCNH24UhPapPBEfwwHa6s_7bi6tqMdA&cad=rja[/url])


Interestig article. There s a nice story related to satsuma cultivars released in sixties mentioned in that article. Professor Pospisil from Czechoslovakia met with japan delegation at symposium at that time and they offered to him and his university in Prague some budwood.
It arrived in 1971 or so trough Japan embassy. It was then encrypted under names J1, J2 ....J6, means Japan 1 etc. and put on tests. For better chance to survive, budwood was also secretly given to 2 experienced growers to test it in thier private colections. I personally saw last week these trees in private collection still alive and kicking. Then it was oficially announced to USSR. Russians asked for budwood, but official statement from CSSR was that budwood did not survived.
After some time the names were released.
J1 - Okitsu
J2 - Matsuyama
J3 - Miyagawa
J4 - Miho
J5 - citrus sulcata
J6 - citrus sunki
Title: Re: Citsuma Prague
Post by: Millet on April 29, 2017, 04:32:55 PM
Ilya11 thank you for the Okitsu, Japan Horticultural Research Station article.  Interesting reading.
Title: Re: Citsuma Prague
Post by: jim VH on May 01, 2017, 11:33:28 AM
Millet,

Stan McKenzie sometimes has grafted Prague Citsumas available.  The one I got grafted -he thinks- on Poncirus rootstock had one small fruit last winter.  It was very good, sweet with a mandarin flavor and no poncirus aftertaste.
Title: Re: Citsuma Prague
Post by: Millet on May 01, 2017, 01:03:15 PM
jim VH, thanks for the tip. I'll contact Stan and ask if he presently has any in stock.  I've known Stan for quite some time.
Title: Re: Citsuma Prague
Post by: Florian on June 23, 2017, 11:43:28 AM
Quick update, my Citsuma has decided to flower for the first time and I am quite happy.
Ilya, what time of year does yours usually flower? I assume mine is so late because it is the first time?
(https://s17.postimg.cc/ml21d50rf/20170623_171045.jpg) (https://postimg.cc/image/ml21d50rf/)
cheers
Title: Re: Citsuma Prague
Post by: Sylvain on June 24, 2017, 06:48:55 AM
You can find flowers all over the warm seasons but main flowers times are spring (one month after poncirus) and now.
Fruits of the first bloom will be ripe before the first freezes but the ones of the second bloom will have to be protected.

At this time of the year, the fruits of the first bloom are marble size.
Title: Re: Citsuma Prague
Post by: Florian on July 03, 2017, 02:34:35 PM
Two flowers have opened and both have four petals but no stigma :o

(https://s22.postimg.cc/6rdrh3qhp/20170703_143719.jpg) (https://postimg.cc/image/6rdrh3qhp/)


Title: Re: Citsuma Prague
Post by: Ilya11 on July 03, 2017, 03:24:10 PM
My Prague never had flowers with functional styles.
Title: Re: Citsuma Prague
Post by: Florian on July 03, 2017, 03:30:29 PM
Good to know, thanks!
Title: Re: Citsuma Prague
Post by: Millet on July 03, 2017, 08:51:28 PM
I wonder if the Prague Citsuma that has incomplete flowers can be "pollinated" with gibbereillic acid the same way clementines are pollinated using gibberellic acid.
Title: Re: Citsuma Prague
Post by: SoCal2warm on July 13, 2017, 11:08:10 PM
From the quick research I've looked into, it seems that Citsuma Prague is most likely a cross between trifoliate and Satsuma mandarin (or less likely a mandarin in the same close category as Satsuma).

I do wonder about crossing Citsuma Prague with 10 degree tangerine, that would be interesting.
Title: Re: Citsuma Prague
Post by: Sylvain on July 14, 2017, 06:30:32 AM
Prague is a chimera of a large flowers poncirus (because I saw it) and a mandarin. The kind of mandarin is not known. We speculate that it is a satsuma because it was found in Prague and the fruits are seedless but the rind doesn't easily separate from the pulp (at least it is not so easy as for satsuma).

We can go farther. It is a periclinal chimera because of the leaves patern and a high stability.
The tree is thorny when poncirus are and mandarins are not. This character is carried by the first layer L1. It means the first layer is from Poncirus L1=P.
The fruit is pure mandarin and the leave margin is evergreen, it means the second layer is mandarin: L2=M.
The leaves center changes in autumn which means L3 is poncirus: L3=P.
So it seems that the periclinal chimerism is of the PMP type.
Title: Re: Citsuma Prague
Post by: Ilya11 on July 14, 2017, 04:06:09 PM
It could be interesting to get it on own roots and try to propagate from root cuttings.
In this case layers will be different.
Title: Re: Citsuma Prague
Post by: Sylvain on July 14, 2017, 07:23:32 PM
Yes I already thought that. It eliminates the L1 if I remember well.
To root cuttings must not be difficult. I shall do it.
What seems harder is to recreate a plant starting from roots only...
I have seen it many times append naturally but never did it in purpose.

If I am right we might obtain a copy PMP or a very near form MMP (without thorns!).
The MMP could be less cold hardy than PMP.
I don't know from which layer the new L1 is created...

Tomorrow I shall start rooting many  cuttings... :-)
Title: Re: Citsuma Prague
Post by: Sylvain on July 17, 2017, 09:15:53 AM
Quote
Tomorrow I shall start rooting many  cuttings...
Done.

Quote
If I am right we might obtain a copy PMP or a very near form MMP (without thorns!).
The MMP could be less cold hardy than PMP.
I don't know from which layer the new L1 is created...
From https://www.ncbi.nlm.nih.gov/pmc/articles/PMC160199/pdf/041089.pdf (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC160199/pdf/041089.pdf) It seems that the shoots are made of L2 or L3.
It means we should obtain MMM and PPP.
No MMP without thorns.  :'(
Title: Re: Citsuma Prague
Post by: Ilya11 on July 17, 2017, 01:25:30 PM
Original L1 will be lost in root cuttings, in most cases it will be replaced by cells from L3, but it could also come from former L2, so MMP at least theoretically is possible. Since Prague is occasionally giving pure poncirus shoots, it is not entirely stabilized periclinal chimera, probably L2 does contain some proportion of poncirus cells.
Title: Re: Citsuma Prague
Post by: Sylvain on July 17, 2017, 06:43:58 PM
Thank you Ilya, very interesting. So we have some chance to obtain something new!  :)
We shall see in two years. One to root the cuttings and one to grow the roots adventices.
Title: Re: Citsuma Prague
Post by: nicolasm on August 05, 2017, 01:26:51 AM
Hi,
i'm an invidicual breeder interested by chimera, so i've came across the Cistuma Prague. Hope i can get a plant this fall and start playing with it. I'm new to citrus as i want only trees that could be planted on my property (-15°C min), so Prague seems to be able to make the deal :)

My hypothesis is that Prague is a SSP chimera (L1/L2 satsuma and L3 poncirus).

L3 : Rose/Blackberry thorns are from L1 but this is a different kind of thorns. "Studying" different chimeras between medlar and hawthorn, i came to the conclusion that spines are from L3. To test this hypothesis, one could root Prague, and make a root cutting to root. The plant should be all L3 and thus should be poncirus.

L2 : Seeds are from F2. As Prague seems to carry few seeds, it would lead to S2 = satsuma. Seedlings should be pure sastuma.
Also L2 + L3 gives leaf form, so if both L2 and L3 where poncirus, i guess leaves would be trifoliate.

L1 : Fruit juice is L1, so from taste it is Satsuma

To my knowledge there is no way to try to mix layers of the chimera to try to get new layer associations
Title: Re: Citsuma Prague
Post by: Ilya11 on August 05, 2017, 05:01:09 AM
To test this hypothesis, one could root Prague, and make a root cutting to root. The plant should be all L3 and thus should be poncirus.
As i wrote above, in most of the cases in root cuttings L1 will be replaced by L3 cells that are very invasive, but it could be  also be formed by the cells from the former L2 that are present in the roots.
L2 : Seeds are from F2. As Prague seems to carry few seeds, it would lead to S2 = satsuma. Seedlings should be pure sastuma.
Also L2 + L3 gives leaf form, so if both L2 and L3 where poncirus, i guess leaves would be trifoliate.
Sylvain demonstrated that fruits and seedlings are pure satsuma
Leaves are formed by all three layers, with L1 forming a leaf margin, this explains the fact that Prague have a very particular foliage.
Title: Re: Citsuma Prague
Post by: Sylvain on August 05, 2017, 07:44:52 AM
Quote
"Studying" different chimeras between medlar and hawthorn, i came to the conclusion that spines are from L3.
Could you give the source of what makes you think so?
Because from what I read  the Crateagomespilus chimera is of the type  crateagus/mespilus/mespilus. It is thorny and the thorns come from crateagus (L1).
https://books.google.fr/books?id=ZVdoUPtqKCIC&pg=PA190&lpg=PA190&dq=Crataegomespilus+origin+of+thorns&source=bl&ots=9Vhk-EzVs9&sig=VPhgI6_t7w53XJ2754bhK7kKETA&hl=fr&sa=X&ved=0ahUKEwj9o6ez-7_VAhVDaVAKHYgRAZs4ChDoAQgoMAA#v=onepage&q=Crataegomespilus%20origin%20of%20thorns&f=false
Title: Re: Citsuma Prague
Post by: Sylvain on August 05, 2017, 11:11:00 AM
Quote
Fruit juice is L1.
Could you give your sources. Please.

In "The citrus  industry" I found few lines going in that way, but it's old (1968):
Quote
In Japan, two citrus forms considered to be synthetic periclinal chimeras have been in existence for some fifty years (Samura and Nakahara, 1928; Takahashi, 1962).   The Kobayashi Mikan is recorded as having arisen at the junction where a satsuma scion was grafted onto Natsudaidai.   This scion was accidently [sic] broken off at its base, after which two adventitious buds emerged, one of which grew into the original chimeral tree.   This chimera produces fruit with rind like Natsudaidai, but with flesh like satsuma.   It is seedy, and seedlings from one fruit were reported to be Natsudaidai (Dr. Yuishiro Tanaka, unpublished).   In this chimera, histogenic Layer II appears to be genetically Natsudaidai, while Layer I should be satsuma.
and
Quote
It appears that a mutant color factor is present in the Thompson in histogenic Layer I; this layer provides at least part of the cells of the juice vesicles

If it is confirmed we could be in presence of MMP as you say.

It means that among the roots adventices we might find many PMP and few MMP. Just the same as if the origin is PMP, because the L1 is dropped off.
In the first hypothesis (PMP) the majority should be identical to the origin and in the second  hypothesis (MMP) the majority should be different from the origin.

The suspense is unbearable!...  ;)

And indeed if the truth is "It seems that the shoots are made of L2 or L3." we shall obtain many poncirus and few mandarines...
Title: Re: Citsuma Prague
Post by: nicolasm on August 05, 2017, 02:19:11 PM
Source of L1 = juice :
Quote
In the citrus fruit, the first germ layer L1 produces
the juice sacs of the fruit and the epidermis of the
pericarp, while L2 produces seeds, segment walls, the
hypoderm and the mesocarp of the pericarp, and L3
the vascular bundles (Cameron et al., 1964; Fost &
Krug, 1942; Kuhara, 1988).

Interactions between different genotypic tissues in citrus graft chimeras
Jinmei Zhou et  al.

Quote
It means that among the roots adventices we might find many PMP and few MMP. Just the same as if the origin is PMP, because the L1 is dropped off.
In the first hypothesis (PMP) the majority should be identical to the origin and in the second  hypothesis (MMP) the majority should be different from the origin.

I dont understand your phrase. Root tissue is pure L3 in trees (unlike in some rhizomes and some other cases) so any root adventices should be pure poncirus.
Title: Re: Citsuma Prague
Post by: Sylvain on August 05, 2017, 06:58:44 PM
Well, it seems that only L1 is lost in the root. That means that L2 and L3 are present.
Do you agree with that?

And thank you for L1 = juice. Very interesting.
Title: Re: Citsuma Prague
Post by: nicolasm on August 06, 2017, 02:54:51 AM
For L1 = juice i'm not so sure.
It seems that L1 is juice sac. I think juice is mostly L1 but can be somewhat modified by other layers (like sugar and acidity level, quoted in the paper). Maybe L2 = satsuma is important to be as close as possible to satsuma flavor. But color of rind and juice is L1, so i guess it is sure that L1 is satsuma (i let you confirm, as i'm a complete beginner with citsuma, satsuma and poncirus).

I guess that when you say F2 and F3 it means L2 and L3. Unfortunatly tree roots are pure L3. Other layers are present when roots are not true root but modified organs (blackberry, potatoes, mint...)
Title: Re: Citsuma Prague
Post by: Ilya11 on August 06, 2017, 06:51:01 AM
It is important to note that we do not have the original Citsuma , but  only grafted plants.
The rooted stem cuttings could produce roots either directly from cambium cells (L3) or from callus  that potentially could involve cells from any layer.
Title: Re: Citsuma Prague
Post by: Sylvain on August 06, 2017, 09:40:06 AM
After one day of research, in "Breeding For Ornamentals: Classical and Molecular Approaches" I found:

(http://pafranceparamoteur.free.fr/datas/perso/Agrumes/Root%20cutting.png)
Title: Re: Citsuma Prague
Post by: nicolasm on August 06, 2017, 03:14:29 PM
It is important to note that we do not have the original Citsuma , but  only grafted plants.
The rooted stem cuttings could produce roots either directly from cambium cells (L3) or from callus  that potentially could involve cells from any layer.

What i've understood is that root tissue is L3, not that it comes from cambium (L3).
Title: Re: Citsuma Prague
Post by: Ilya11 on August 06, 2017, 06:12:32 PM
All three embryonal layers in higher plants are pluripotent. They are able to generate callus and it  is giving  both stems and roots. In this case, roots are not necessary belong to original L3.
Moreover, while L1 is quite stable, L2 and L3 are constantly invading each other.  This explains uneven margin in decorative albino chimeras (L1=green, L2=albino, L3=green)
https://uwaterloo.ca/biology/sites/ca.biology/files/uploads/files/Lecture%207%20for%20students.pdf (https://uwaterloo.ca/biology/sites/ca.biology/files/uploads/files/Lecture%207%20for%20students.pdf).
Title: Re: Citsuma Prague
Post by: snek on January 10, 2018, 01:28:01 PM
„Hybrid (Unshiu x P. ITSZ Prague“ is the greatest mystery among citruses for me.
Is it a hybrid? Is that a chimera? Or maybe something else? Any mysterious play of nature? I do not know.
Many of the previously published information I have discovered. Here I will try to summarize the most important thing about this cultivar I know.


1981:
I started growing citrus

1987:
The first literary reference to the hybrid. "Citrus Growing", c. SZN 1987, Ing. Stanislav Husak, CSc., Doc.Ing. Vladimír Táborský, CSc., Prof. Ing. Pavel Valíček, DrSc., Page 21 - 2.2. Fundamentals of genetics and citrus breeding. Photo 45: "Hybrid (Unshiu X Poncirus trifoliata) bred on ITSZ Praha".
It must be said that this was the first and at the same time the last mention of this hybrid in literature in the Czech Republic.
Note: : Prague is the capital of the Czech Republic. ITSZ is a university. Her name is the institute of tropical and sub-tropical agriculture.
Previously, many books on citrus growing have been published in the Czech Republic. Until 1993, a magazine on citrus growing was published- 5 times a year. The Citrus Growers' Association had 10,000 members (the population of the Czech Republic is 10,000,000 people !!!). In a country where citrus trees can not normally be grown !!
Why it was not published anywhere else is a mystery to me.

1989-1996:
I have seen hybrids several times but Cold Hardy citruses were outside my area of interest. I also met with many interesting hybrids, mostly from the former USSR.
I've heard it repeatedly : Badly growing. It does not produce. If you want the weeds in the greenhouse, grab a bud.

2004: Mr. Zdeněk Černoch began to make his collection of citruses, which now belongs to one of the largest in Central Europe. Especially cold hardy citruses. Aroused great interest in them in the Czech Republic.

2007:
I was also interested for cold hardy citrus. The source of grafts was mainly Broža Petr and Zdeněk Černoch. The Bud from which my plants originated was taken by Peter Broža. From its small 15cm large plants growing in the middle greenhouse.

2009/2010:
Plants at Petr Broža and Zdeněk Černoch died in the winter. They have recovered from me. All plants sold by Zdeněk Černoch all over Europe from 2010 until 2014(?) they're out of my buds. Sometimes later, Zdeněk Černoch brought the other buds from France. I do not know from whom.

2016:
I managed to contact Prof. Ing. Pavel Valíček, DrSc., Author of the book from 1986.
He told me that the hybrid was bred prof. Pospíšil. Classical crossbreeding and subsequent selection. Sometime between 1971 and 1977.

Prof. Pospisil is unfortunately dead.

My friend in Prague visited Mrs. Rozinková, who was a collaborator of prof. Pospíšil. She's an older lady, no new information more. She just confirmed the information from Mr. Valíček. The new information was just that there were also experiments with seed irradiation and any others

From information from Petr Broža I know that B. Voss was wearing some citrus from ITSZ greenhouses in Prague. Whole plant with roots. It was supposed to be the hybrid Uhshiu X P.T. ITSZ Praha. It is certain that many other similar hybrids originating in the former USSR were in the ITSZ greenhouses at that time.

Information from Mr. Hlaváč (Head of ITSZ Greenhouses in Prague) - He confirmed that B. Voss took some citrus plant from the greenhouse. It was not a hybrid but something else. The original plant is still growing in the greenhouse of ITSZ Praha. If I want to, I can come and see.
Meanwhile, I did not have time for this (greenhouses are not publicly accessible, the visit needs to be arranged in advance).

In 2016, I accidentally managed to provide at MU Brno (Masaryk University, the Faculty of Natural Science) a cytometric analysis of the genome size of the hybrid. Incl. comparison of genome size Unshiu and P.T and F.D.
The analysis was repeated three times using different parts of the hybrid tissue. For all samples, only one peak was found in the histogram. This means that the plant has only one genome, ie. the plant is of hybrid origin. The chimera should have two peaks in the histogram because it carries two different genomes. Separately tested parents of the hybrid have the genome size significantly different, the histogram would be clearly visible.
However, cytometric analysis of the genome size can not be, for many reasons,  a 100% result.
---------------------------------------------

For different growers, the hybrid is completely different.

The Sylivian plant grows almost up. My plant a willow. Without counting the height of rootstock, they are approximately the same size. I have to constantly shape the plant. Otherwise, it would look like the second and third my plant that crawls 40cm above the ground.

My and other known breeding plants are free of seeds. Sylvian seed produces.

For me, Bi- and Tri-foliate leaves fall in autumn only in older plants, not in young ones.

Sylvian plant blooms in spring twice, my only once.

My plants show mild symptoms of psoriasis or leprosy. But psorosis or leprosy is definitely not.

At Sylvian seedlings produce non-trifoliated plants. I wanted to verify this very much. Except for natural pollination, all the flowers were artificially pollinated. No seeds. Not a germ.

The plant in Vienna transforms itself into a pure trifoliate.



It is totally crazy.
Title: Re: Citsuma Prague
Post by: mikkel on January 10, 2018, 03:15:15 PM
Vice versa: Could a common hybrid behave like this?
Title: Re: Citsuma Prague
Post by: Ilya11 on January 10, 2018, 03:22:01 PM
In  experiments done in MU Brno one symmetrical peak of genome size was observed, but they have not performed a crucial control demonstrating that an artificial mixture of nuclei from poncirus and unshiu  gives two distinct genome sizes.
Title: Re: Citsuma Prague
Post by: SoCal2warm on January 10, 2018, 04:47:49 PM
It's not as likely, but one possibility is it could be a triploid, if one of the gametes was unreduced. (This can occasionally happen by natural processes) That could potentially have left the entire genome of one of the parents intact. (In that case it would be 2/3 poncirus and 1/3 mandarin, or 1/3 poncirus and 2/3 mandarin)
Being a triploid would also explain lack of seeds or low seed count.

(for those of you who may not understand, occasionally during production of the plant's reproductive cells meoisis fails to take place, and then the reproductive cell has the full set of two chromosomes, so when it later combines with another reproductive cell the resulting zygote will then have three sets of chromosomes, instead of the usual two that most citrus plants have)
Title: Re: Citsuma Prague
Post by: snek on January 10, 2018, 04:53:45 PM
In  experiments done in MU Brno one symmetrical peak of genome size was observed, but they have not performed a crucial control demonstrating that an artificial mixture of nuclei from poncirus and unshiu  gives two distinct genome sizes.

That's true, I agree.
Purely mathematical: Under certain circumstances, only one peak can be found at the chimera. At the same time it has to be said that the peaks can be really two. It depends only on how the initial curves of the separate elements are steep. The problem is that I do not have histograms. From histograms, this could be further investigated. The Results was communicated to me only by phone and I received one short e-mail.

I'm not a botanist. I do not know how genomic size histograms appear in plants on a flow cytometer. However, if I had to estimate, I would think that the proportion of genomes of different size (5%) would be very close to 0% of the representation. If this reasoning is correct, there must always be two peaks on the histogram. For a chimera and a mixture of separate components.
Title: Re: Citsuma Prague
Post by: snek on January 10, 2018, 05:10:14 PM
SoCal2warm  : Is it possible to verify it? If so, how? I'll try to get it.

This applies to all suggestions that it could explain the
Title: Re: Citsuma Prague
Post by: snek on January 10, 2018, 05:22:49 PM
Mikkel : I do not know. I'm not a botanist or geneticist.
I have a certain theory. But she's more crazy than the plant  :) :) :)
Title: Re: Citsuma Prague
Post by: Ilya11 on January 11, 2018, 03:44:38 AM
Snek,
I have the same problem with theguy from Brno, his first reply was very complete and helpful, but he has not replied to my further questions. I am not a botanists either, but in my previous life ( I am retired now) I was working in Molecular Biology and Human Genetics and know perfectly the method that was used by them. It is not the best way to resolve the chimerism, the simplest one is just to use one or two plastid DNA marker that distinguish poncirus and unshiu.
Title: Re: Citsuma Prague
Post by: snek on January 11, 2018, 05:44:42 AM
Ilya,
the same was with me. First was very complete and helpful, but later he has not responded.
I just gave the samples, I took them to the university lab, I defined what I want to know. I had doubts, and so it was repeated again.

I received the results by e-mail. Three short sentences.
I asked for details. Without an answer. After many urgings, I learned that he thought your colleague had already sent me or yes, yes, I'll send. I just received a list of what was tested for the first time and the second time. I do not have anything to do with the third repeat tests. Just one sentence in an email.

The list that I received is also an artificial mixture of "C. unshiu 'Planellina + ITSZ doublelist". Logically I assume that if there was only one peak in the histogram, I would have been told that the analysis was not conclusive. But I was told that the data obtained eliminated chimerism. This should mean that there were two peaks in this sample. If this is not a big mistake. Direct ignorance. It is possible, but I do not want to believe it.
Title: Re: Citsuma Prague
Post by: Sylvain on January 11, 2018, 06:34:42 AM
Last news. In the crop of this year most of the fruits are flatten at the distal end, like satsumas. The fruits of previous years were near-spherical. I find from 0 to 3 seeds per fruit. The seeds are also different. They are big and we can see trough the thin testa the green cotyledons. They look poly embryonic.
The pulpe is still the same: a pure mandarine.
Title: Re: Citsuma Prague
Post by: Ilya11 on January 11, 2018, 07:43:32 AM
Sylvain,
I do not fully understand:does this mean that seedlings that you showed were from monoebryonic seeds with white cotyledons?
Title: Re: Citsuma Prague
Post by: snek on January 11, 2018, 08:55:05 AM
I wanted so much to have seeds in the fruit. That's why I polished all of them. I did not care about nature. Unfortunately, no seeds.

I wanted to see the seeds and wanted to plant them. Just like Sylvian did.

In my opinion, this is the only way to get answers to some questions about the plant without the use of specialized workplaces and laboratories.
Title: Re: Citsuma Prague
Post by: snek on January 11, 2018, 09:38:21 AM
I have to ask.
Have you ever seen a real chimera for yourself? I do not think so.
Do you know or even have some citrus chimeras from the former USSR?
I've seen some of it in very old photos (50's or 60's). And it looked very convincing. E.g. orange, sometimes with trifoliate leaves. I saw some at noon. And it was always a plant without the other part - a pure orange. When cutting the screws, the second genome remained on the original plant. Is it even possible? If so, could it happen to the hybrid (Unshiu X P.T.) ITSZ Praha? If it's a chimera.
Title: Re: Citsuma Prague
Post by: Sylvain on January 12, 2018, 09:32:04 AM
Ilya,
> does this mean that seedlings that you showed were from monoembryonic seeds with white cotyledons?
No, not at all. The seedlings I grow all come from one seed, the only one I had in many years. I Think the cotyledons were green but the main thing is that the seed looked like a "normal" citrus seed, like a lemon seed. The ones of this year are very different. They are big and puffy and we can see the green cotyledons through the testa. It makes bumps on the seeds making me think they are polyembryonic but I still didn't open one. They exactly look like yuko seeds that are very polyembryonic.
The 'work' of these days is to eat the fruits and collect the seeds. Later I shall take pictures.

Snek,
> Hybrid (Unshiu x P. ITSZ Prague“ is the greatest mystery among citruses for me.
It will remain like this as long as you shall consider Prague chimera like a(n) Hybrid.
When you will think of a chimera, everything will become clear and even evident.

> I've seen some of it in very old photos (50's or 60's). And it looked very convincing. E.g. orange, sometimes with trifoliate leaves.
If you know an equivalent chimera with orange please immediately take cuttings ( and send me some ;-) ).

> When cutting the screws, the second genome remained on the original plant. Is it even possible? If so, could it happen to the hybrid (Unshiu X P.T.) ITSZ Praha? If it's a chimera.
I am not sure to understand this sentence but if you mean "is it possible to obtain a pure mandarine fruit from a(n) hybrid of poncirus", the answer is absolutely 'NO' for an hybrid and absolutely 'YES' for a chimera!

It is the same for a pure trifoliate branch, the answer is absolutely 'NO' for an hybrid and absolutely 'YES' for a chimera!

It is the same for monofoliate polyembryonic seedlings and for everything we can see on the prague. It is always NO for a hybrid and always YES for a chimera.

Title: Re: Citsuma Prague
Post by: hardyvermont on January 12, 2018, 01:25:30 PM
Sylvain, Ilya, Snek, and everyone else,
When do Prague fruit ripen? Before freezing weather?

Thanks,
Alan 
Title: Re: Citsuma Prague
Post by: Sylvain on January 13, 2018, 05:50:09 AM
Let's say for Christmas.
This year I picked them the first days of the new year but many people would feel them overripe, very sweet with low acidity.
Title: Re: Citsuma Prague
Post by: snek on January 13, 2018, 11:17:06 AM
For me Christmas / New Year. It is still outdoors, but protected by the sail.

Title: Re: Citsuma Prague
Post by: Zitrusgaertner on February 13, 2018, 06:58:37 AM
Sylvain wrote:
"It was from Petr Broza. At this time (2008/2009) we were only three (with B. Voss who found it) to have it."

I had it aswell. Mine grows in open soil grafted on 1m Poncirus in my Viennese Garden. I reported about the "strange thing" in the US-forum which is now down. The motherplant shown there is still potted. The chimera is hardy at least down to -15°C.
Sylvain, may I borrow the pics from you? I have a presentation about "strange things about citrus" in a few weeks.
Title: Re: Citsuma Prague
Post by: Ilya11 on February 13, 2018, 01:06:16 PM
Sylvain wrote:
"It was from Petr Broza. At this time (2008/2009) we were only three (with B. Voss who found it) to have it."

I had it aswell. Mine grows in open soil grafted on 1m Poncirus in my Viennese Garden. I reported about the "strange thing" in the US-forum which is now down. The motherplant shown there is still potted. The chimera is hardy at least down to -15°C.
Sylvain, may I borrow the pics from you? I have a presentation about "strange things about citrus" in a few weeks.
Robert, welcome to this board :D
Title: Re: Citsuma Prague
Post by: Zitrusgaertner on February 13, 2018, 03:31:03 PM
I'm glad to meet you all again.  ;D
Title: Re: Citsuma Prague
Post by: Sylvain on February 14, 2018, 06:53:00 AM
Indeed you can use any of my pictures.
I look for yours but as they were on postimg.com, they are lost.
The only one I found is this one:
(http://s1.postimg.cc/e4q733kf2/IMG_1808.jpg)
Title: Re: Citsuma Prague
Post by: Zitrusgaertner on February 15, 2018, 08:07:36 AM
This is the right picture. The best I have. You can see two Poncirus-Fruits on it, but it is "Prague" ;) By the way I have cut away the offspring and grafted it on a PT-seedling. It flowers but always throws away its fruits. But they are PT -no hope of anything else.
Title: Re: Citsuma Prague
Post by: snek on April 26, 2018, 01:11:44 AM
Flowering


(https://s18.postimg.cc/cyv0d8g11/2018-04-25-a.jpg) (https://postimg.cc/image/cyv0d8g11/)

(https://s18.postimg.cc/6xxbg614l/2018-04-25-b.jpg) (https://postimg.cc/image/6xxbg614l/)

(https://s18.postimg.cc/92hoh9i6t/2018-04-25-c.jpg) (https://postimg.cc/image/92hoh9i6t/)

(https://s18.postimg.cc/43u62q6o5/2018-04-25-d.jpg) (https://postimg.cc/image/43u62q6o5/)
Title: Re: Citsuma Prague
Post by: Sylvain on April 26, 2018, 02:56:23 AM
Very nice! Mines are at the same state.
Did you notice that the new growths go straight to the sky? your plant went out of the "bushy state".
Title: Re: Citsuma Prague
Post by: Ilya11 on April 26, 2018, 03:43:22 AM
It looks like stamens are yellow and probably contain fertile pollen :o
Very uncommon for satsumas.
Title: Re: Citsuma Prague
Post by: Zitrusgaertner on April 26, 2018, 01:28:46 PM
Snek, your Prague has kept ists leaves. Very interesting. Mine gets rid of them in autumn.
Title: Re: Citsuma Prague
Post by: snek on April 26, 2018, 04:22:03 PM
Sylvain :
It will come to me the same as other years. First up, but quickly turn down. It will be seen later.

Ilya11 :
Rather I think not ( The image can not be pasted now, I will try later).  I'll watch.
But stigma is not sticky. Or just little.
(https://s18.postimg.cc/nxgdpg6x1/IMG_2953u.jpg) (https://postimg.cc/image/nxgdpg6x1/)


Zitrusgaertner :
Part of the leaves will always remain over the winter.

Title: Re: Citsuma Prague
Post by: Florian on April 27, 2018, 03:10:31 AM
Here's hoping mine will make fully functional flowers this year. It is not yet flowering but there are a few buds.
Title: Re: Citsuma Prague
Post by: snek on April 27, 2018, 05:55:46 AM
Even fully functional flowers do not mean they will be fruit.  >:(
The first flowering in 2011 ... first fruits in 2017 ! About of 200 flowers
Title: Re: Citsuma Prague
Post by: Zitrusgaertner on April 28, 2018, 05:48:05 PM
You have to feed the Prague very well if you are eager to get fruits  ;)
Title: Re: Citsuma Prague
Post by: Florian on July 29, 2018, 02:37:04 PM
Well, at least there are stigmas in some flowers now. That's a progress.. ;D

(https://s22.postimg.cc/yn18hrszx/20180729_192743.jpg) (https://postimg.cc/image/yn18hrszx/)
Title: Re: Citsuma Prague
Post by: Millet on July 29, 2018, 09:30:15 PM
Florian, as they say...."Good things come to those who wait".