The Tropical Fruit Forum

Pagnr gave a lot of useful information.  I want to add a bit more.
He gave an example of a triploid hybrid with A, B, and C sets of chromosomes.  And he treated them as if each set stayed together.  In fact each set has 9 chromosomes  A1, A2, A3, etc.  B1, B2, B3, etc.  and the same for set C.
A1, B1, and C1 chromosomes are similar having evolved from an origional ancester X with chromosomes X1, X2, X3, etc.
A1, B1, and C1 are still enough alike that one can replace another and still be viable.  But they will be different enough that some, about 1/9, of the traits, will be from the the species that donated that chromosome.  So any pollen grain should have a 1, 2, 3, 4, 5, 6, 7. 8, and 9 but not always from the same species.  One might be A1 B2 C3 A4, B5 C6, A7, A8, B9. o any other combination having one chromosome of each number.  A few of the combinations might not be able to survive, but most will.  A few will be what you had hoped for, or at least a step in the direction.  Most are rejects.

Now another complicacation.  A1, B1, and C1 chromosomes don't stay as they were when you started.  During the formation of pollen and egg cells crossover happen.  I don't know how often they happen in citrus but the crops I have worked usually have about 2 per chromosome per generation.

chromosome from one species has genes
ABCDEFGHIJKL

chromosome from a different species has genes
abcdefghijkl

after a crossover you have
ABCDefghIJKL
abcdEFGHijkl

This exchange usually happens on each chromosome pair per generation, in a different location each time.  So the deck slowly gets shuffled/

Good luck!  Sounds like a good cross.

I commented some time ago that an F1 hybrid of finger lime x Ponciris+ might have a market.  I've been thinking more about it lately.

I do what Millet and Poncirisguy said.  If I need to mow or do garden work I do that while a pot is soaking.  Or reading a good book works too.

I was thinking about that cross Till.  It doesn't fit in with my breeding plans or goals.  But it would certainly interest me.

Good information.  Thank you.

Sounds like Turunji is a bit harder than some citrus on their own roots.  Or perhaps they are too often pot bound by those that sell them.  I am in the process of loosing mine I bought from Logees.  I think I'll try to save it by grafting in some extra roots using Ponciris seedlings.  Mr. Hong in Wichita KS gave me 100 Ponciris fruit last fall and they average about 30 seeds per fruit, so I have plenty to spare.  I also have seedlings from the last 2 years, more than I have scions for.
Here is where I got the idea.
https://tropicalfruitforum.com/index.php?topic=48828.0

A new way to make periclinal  chimeras in citrus is given here.
日 植 病 報 60: 82-88 (1994)
Ann. Phytopath. Soc. Japan 60: 82-88 (1994)
OK,  1994 isn;t new but it is new to mr,  The procass was developed to give disease resistanc in citrus by giving a good variety a coating of a disease resistant variety,  But it seems to me it might work on making good citrus varioties a coating of a cold tolerant variety like ponciris,  The publication says 1/6 of plants made this way were periclinal chimeras,
One would need to use a good varity of citrus that has nucelar seeds,  No problem finding those,
I don't expect the rresulting plants to be hardy in one 6 where I live,  But maybe zone 7 or 8?  Maybe anywhere PPrague is hardy?

As a child and young man I kept bees.  I like them and I like honey.  But my citrus "orchard" is on the edge of town ad bees close to a population of humans seems a bad idea.  I know at least one neighbor who is allergic.  So I'm thinking of buying a start of  native stingerless bees.  I know that some temperate zone fruit orchards are using them with good results.  Are they being used successfully with citrus and other fruits?
And as a breeder who wants masses of crosses, I'd like bees to do some of my work for me.

https://tropicalfruitforum.com/index.php?topic=29541.50

Perhaps this was one of the threads that got you interested.  Though these crosses were not with P+, they could be useful.  While I haven't read of test crosses to prove it, it seems like the difference between P+ and other ponciris is a single gene.

So are you going to be offering seeds for sale?

Yes, I;m interested again.  Walt.

I have also received free seeds for my breeding program.  I have given too, but less than I received.  I'll send some when I have them