Why no blood citranges?

[till]

Hello,

I am asking myself for a while why we do not have blood citranges - so far as I know - although Ruby orange was often used in these crosses. Has anybody an explanation?

Till

[kumin]

Ruby Blood Orange is an inconsistent producer of pigmented flesh. There are areas where it never develops the desired red coloration.

Ruby, being an unreliable producer of flesh color, will have it's genetic contribution halved when used as a parent in hybrids.

I suspect the best chance of recovering pigmented flesh progeny from Ruby/trifoliate crosses would be in the F2 selfed, or in back cross to Ruby populations.

Among such F2 hybrids, I see 3 individual plants that develop a purplish cast on the foliage as a cold response during Winter. This may, or may not indicate flesh coloration cold response, when the trees become mature enough to begin fruiting.

[Laaz]

If I were to try a cross, I would start with something like this...

[till]

Oh, that looks really bloody. I thought of crossing Moro and Poncirus. But my Moro never got seeds. Now, I tried Amoa8 x Poncirus, but fruits are not ripe.
What you wrote about the inconsistent pigmentation of Ruby was also in my mind. But is it the whole story? I mean Valentine is very pigmented and is also offspring of Ruby orange. Was it just luck that it has such a strong pigmentation?
I am excited what fruits your 3 F2 hybrids will have!

[ilya11]

Till, why not to try a reverse cross with poncirus as a mother. Swamp Lemon is giving a lot of zygotic seedlings.

[jibro]

There is also mandarine Trabut if you want create bloody Citrandarin, this fruit is from Petr Broza greenhouse, February 2019

[ilya11]

Jibro, I always thought that Trabut is the same as AMOA8

[jibro]

I have no idea, Petr got it from Edouard Mazzola(Menton, France) as Trabut 10 years ago, btw he also got here Tangelo Melinghina, I can't find any info about this variety (beside Czech source Adavo and people who purchased it from Adavo)

[till]

Ilya and Jibro,
Good suggestions. I prefer Poncirus as motherplant in fact but had the bad luck that my varieties did not produce hybrid seedlings. But now I have a Swamp Lemon with flower buds, too. It will bloom next year. Thank you, Ilya for the information that Swamp Lemon has many zygotic seeds. Then I MUST try the cross with Moro and / or Amoa8.
By the way, how is your Swingle5Star x Moro doing, Ilya?

[ilya11]

They are growing well, but a little bit slower than hybrids with Tarocco. The largest is around 150cm high, now mostly monofoliate.

What I found in general with crosses of 5star to conventional citruses, due to capacity to generate large size populations and early selection it is quite easy to find completely hardy hybrids without poncirus smell of their leaves.

But most of them still have some degree of bitterness, in many cases stronger than for fruits of 5star.

[roberto]

Dec 7, 2020 14:37:07 GMT -5 ilya11 said:

They are growing well, but a little bit slower than hybrids with Tarocco. The largest is around 150cm high, now mostly monofoliate.

What I found in general with crosses of 5star to conventional citruses, due to capacity to generate large size populations and early selection it is quite easy to find completely hardy hybrids without poncirus smell of their leaves.

But most of them still have some degree of bitterness, in many cases stronger than for fruits of 5star.

Stronger than 5Star? But 5* in fact is very bitter. Is there any escalation possible?

[ilya11]

The pulp of 5star is bitter due to internal oils. In my climate 5star juice is only moderately bitter after sediment containing oils was removed after night in freezer. Actually, it gives an excellent curd and citrumelo pies.
The same was also observed by Sylvain.

[till]

Breeding hardy and tasty citrus is easy in theory but tricky in practise. What a pity that bitterness is often increased. Did you made the same observation when you crossed with oranges and with mandarins? I have read somewhere in a book on citrus genetics that the cross sweet orange x sweet orange often results in bitter offspring whereas the cross sweet orange x mandarine in much more promising.

But still, even if a blood citrange or Swingle5Star x Moro would badly taste (what I believe is likely) it would be a possible step towards something hardy and better tasting.

[ilya11]

I have several such hybrids with mandarins, but none has flowered yet.

[till]

It remains exciting...