PT-plusXValentine cross

[Ilya11]

Probably succeeded to have it.
It was done with castrated  PTP flowers pollinated by Valentine pummelo. I tried also another way, but failed.
This year was supposed to be the last to try any cross with PTP, previously the seedlings although different in vigor were rather uniform in the shape of leaves and overall look alike.
Now only one third of them (I am germinating 85 seeds) look like those of poncirus, the rest are clearly different.



Putative nucellar seedling to the right. Red arrows point to the tiny unfoliate alternate first leaves typical for pure poncirus seedlings.

[a_Vivaldi]

Now that's an interesting cross.

I assume the motivation here for the larger, juicier fruit + red coloration. Pigmented pomelo is used rather than a blood orange because of better results from poncirus hybrids with pomelo rather than orange, yes?

[Till]

Very nice, Ilya. I would say: definitely hybrids. Then you have a chance of about 50% to get sweet fruits from the hybrids because of the Siamese Sweet genes. Bernhard Voss has a sweet Chandler x Poncirus cross. How sweet the fruits will be we will see. But 50% should at most have half of Poncirus acidity.
Cf. our discussion about the inheritance of low acidity: https://citrusgrowersv2.proboards.com/thread/728/inheritance-low-acidity
Very good cross. I wish I had done it myself.  Well, perhaps we can exchange pollen in about ten years when my Chandler crosses are flowering (Chandler x (African Shadock x Poncirus) & C. ichangensis x Chandler). Then we create the super sweet hardy citrus. 

[Ilya11]

Now that's an interesting cross.

I assume the motivation here for the larger, juicier fruit + red coloration. Pigmented pomelo is used rather than a blood orange because of better results from poncirus hybrids with pomelo rather than orange, yes?

Valentine is a very special variety with genes for two types of internal pigmentation and a gene for acidless feature.
At least in the case of combination with other cultivars of citrus it is able to diminish the acidity even when present in one copy.
I hope that this will be also a case in  poncirus hybrids.

[Pandan]

Congrats on the success! I was planning on the same cross.

[BorisR]

Great, Ilya!
I see everyone wanted to do the same 😊 I also got myself Valentino a couple of years ago, but it's still far from flowering. I believe Valentino gives zygotic seeds. I wonder why the reverse crossing failed? A large style?

[Ilya11]

Great, Ilya!
I see everyone wanted to do the same 😊 I also got myself Valentino a couple of years ago, but it's still far from flowering. I believe Valentino gives zygotic seeds. I wonder why the reverse crossing failed? A large style?

PT-plus cross also  was early failed
It seems to me that generally crosses with poncirus are not easy to perform.
Valentine is abundantly flowering, but fruit set is quite limited, most fruitlets drop rapidly.

[mikkel]

Well done! Let`s hope for a short juvenility. 
Is Valentine more effective than Chandler to diminish the acidity in its progenity?

[poncirsguy]

valentine drops most all flowers for in ground trees and for potted tree they often keep flowering till they die.  It will drop golf ball size fruit to get energy to continuing its flowering.  I have to pick very small buds if I want the tree to hold fruit

[Millet]

Ilya11,  I notice you just push your seeds partially into the soil, with the top half of the seeds still in the air.  I have always buried my seeds  1/2 to 1 inch into he soil.  I further noticed your method of seed germination was very high, and still applied enough moisture to the seeds for a high germination.
Thank you for your post.

[Ilya11]

Millet,
The seeds are germinated in zip locked packets in slightly moist  perlite at 30C. After root appearence they are transfered on the surface of substrate in covered pots.

[tedburn]

Interesting combination Ilya, Valentine excellent pomelo and quite early maturity,
mine  have  been excellent foer eating mid January.
So my question is are the fruits of PT plus also without poncirus taste ?
Curious how your seedlings come out ? Beginning with your hardiness tests
and leaf taste ?

[Ilya11]

They are just germinating.
PT-plus when fully ripe (can be detached easily) does not have internal oils and poncirus aftertaste.

[sc4001992]

FYI, I have a very large tree that is mainly Valentine and Reinking pomelo. If any of you would like me to save some pollen i can try and send it to you for your next experiment. I always get many Valentine fruits on my large tree. I was thinking of cutting the tree down to half the size next week so let me know if any of you would like the pollen then maybe I will leave the tree alone to get more pollen. Tree is about 30 yrs old.

[Till]

HI SC4001992,
I would like to get pollen. Can you dry it und send it to Germany? I want to pollinate C. ichangensis, Dunstan Citrumelo and Poncirus with it.

[sc4001992]

When my tree has flowers I will save it for you, just give me the proper method to store it for you. Right now my tree has many large fruits hanging.

[sc4001992]

Ilya11, can explain to me what you mean by two types of internal pigmentation?

"Valentine is a very special variety with genes for two types of internal pigmentation and a gene for acidless feature."

Are you referring to the flesh color sometimes being red inside on some fruits, but others are yellow? My fruits do not all have the red pigmentation, some are completely yellow flesh, but both types seem to taste about the same to me. My tree usually has about 50 fruits that hold on the tree so I need to thin it down to about 30 each year or it will break my branches from the weight.

[Ilya11]

Sorry for the mistake.
Valentine contains only the gene of anthocyanine pigmentation coming from Ruby orange ancestor.
The other type of pigmentation due to the presence of lycopene is absent.

[alexmed95]

Probably succeeded to have it.
It was done with castrated  PTP flowers pollinated by Valentine pummelo. I tried also another way, but failed.
This year was supposed to be the last to try any cross with PTP, previously the seedlings although different in vigor were rather uniform in the shape of leaves and overall look alike.
Now only one third of them (I am germinating 85 seeds) look like those of poncirus, the rest are clearly different.



Putative nucellar seedling to the right. Red arrows point to the tiny unfoliate alternate first leaves typical for pure poncirus seedlings.

Hi Ilya,

Knowing that you have germinated 85 seeds, how will you decide which one to move forward with? Assuming you won't grow 85 seedlings until they are mature enough to bear fruits... What is your usual selection process?

Thanks

[Ilya11]

I shall probably select by forced freezing of -8C at the 15 cm stem stage, like I do for the rest of my hybrids.

[kumin]

Ilya, what time duration do you subject the seedlings to -8C? Do you do any cold pre-exposure prior to the testing? Your procedure certainly could reduce time, space and materials expended on doomed seedlings. Thanks

[Ilya11]

As an acclimatation step I  expose pots to outside conditions for two weeks during February and March. Usually average temperatures in this period  change from 8 to 12°C. 
In temperature  controlled freezer the pots with seedlings are kept at 0°C overnight, -4.5°C for 3 hours and -8°C for four hours. Then the are left with power off overnight. In 6 hours the soil temperature of pots  reaches 0°C. 

[tedburn]

Hello Ilya,
did you also report about your freeze test of this cross, how
much of the seeds survived after the test ? It would be interesting to
see some actual pictures of these crossed plants and there leave shapes.
Thanks Frank
Modify message

[Ilya11]

One hundred forty five seeds gave 131 seedlings, around half of them were considered nucellar,  22 survived the freezing test, but later on some stopped to grow, so finally I have  15 plants thriving in the ground.
 I shall show the pictures ASAP.

[tedburn]

Thanks very much Ilya,
very interesting results 👍,
nice hardiness percentage.

[BP]

Millet,
The seeds are germinated in zip locked packets in slightly moist  perlite at 30C. After root appearence they are transfered on the surface of substrate in covered pots.

Very interesting thread thank you for sharing your process. I'm going to have to try the bagged perlite trick as well as putting the bottles over the pots for extra humidity. Have you noticed the humidity makes a big difference in your seedlings? Are you still using this approach? Thanks again

[Ilya11]

Yes, it is definitely working to force non-stop grow of young seedlings.
Also,high humidity prevents red mite infestation.

[Ilya11]

As promised, recent photos of these seedlings

[a_Vivaldi]

Those are looking good and healthy!

One of those grapes in the background look to have leaves like some of the American species. What variety is that?

[Ilya11]

You have a good eye.
It is Frontenac, hybride of V.riparia and  Landot noir. Completely resistant to phylloxera and fungal diseases here.

[tedburn]

Very impressive size of the seedlings Ilya.
Your raising method with germination, freeze test ( selection)
and transplanting inground seems very effective.
My Chandler x Bloomsweet lack far behind yours though same age concerning size,
but one total winter inground for one year old seedlings
seem to much for the young roots.
My Yuzmelo x Bloomsweet has trespassed them by growth, but they
havent yet selected by freeze test.
Was your leave taste test good ?

Chandler x Bloomsweet left side, Yuzmelo x Bloomsweet right side