Author Topic: Poncirus hybrid crosses  (Read 3678 times)

Walt

  • Sr. Member
  • ****
  • Posts: 329
    • USA, Kansas, Kanopolis, zone 6
    • View Profile
Re: Poncirus hybrid crosses
« Reply #50 on: August 23, 2023, 12:29:31 PM »
Yeah, cold hardy citrus breeding is no walk in the park.

Again, one of the biggest roadblocks is high rates of nucellar seed. What probably needs to happen at some point is someone needs to make a dedicated effort to breed zygotic seed into cold hardy citrus.

To do that, you'd want to take a bunch of fully zygotic varieties like Meyer lemon, ichang papeda, one of the more cold hardy pomelos, rough Seville orange or some other zygotic sour orange, then some combination of (1) breed then with each other, using ichang papeda as your main source of cold hardiness and then screen your F2 generation for hardiness (2) cross them with the handful of zygotic poncirus hybrids (eg the SuperSour series of rootstocks) and again screen for cold hardiness in the F2 generation, (3) find out which fairly cold hardy hybrids have one fully zygotic patent, ichang lemon for example, and cross it with your zygotic varieties, then screen the F1 generation for zygotic seed, and (4) cross them or some of your good F1s and F2s with the nucellar but very hardy hybrids and varieties like 5*, Dunstan, Changsha, then backcross those F1s with your fully zygotic plants again so that hopefully you'll have some fully zygotic F2s.

Lots of options, but none of them would get you results in a single generation. You'd probably need another two generations to then select for the best cold hardiness. That's at least a lifetime of breeding work. However, were someone to do this, it would make cold hardy citrus breeding much, much easier. And if you went for an four options, and were sure to include a wide variety of sources of zygotic seed (lemon, pomelos, sour orange) you'd end up with a lot of genetic diversity to work with to get the fruit quality you'd need for something not just edible, but good.

8B is probably one of the better zones for attempting a project like this.


  Nothing against what was said above, if you want that much genetic variation in your population.  But there are already 4 mostly zygotic mandarin x Ponciris hybrids in use.  US 1279, 1281 and 1282 are more than 95% zygotic, and 852 is about 85% zygotic.  And Kumin has some F2 citranges that have survived 4 (or is it 5 now?)zone 6 winters.  And he has collected some citrimelos and such to bring into his population.  I think he is closer to success and will have an easier time than is being talked of here.
I am trying about the same way but I'm way behind him, in spite of his sharing his stock with me.  We are both in zone 6, but our climate and soil are different, and our time and space are different.
Also I am also working toward a hardy finger lime.  I didn't know that Australian citrus don't cross well with Ponciris.  However, at least one finger lime x Ponciris exists in Florida.  They aren't sharing it.  At least not with me.
I hope my saying this keeps others from trying to breed hardier citrus, and trying different methods, and working toward different goal.  I have been in touch with someone in Tennessee zone 7,  working on hardier kumquats via kumquat x Ponciris.  I think he will be successful in a few generations.
I wish success to all of us.  And have fun!

a_Vivaldi

  • Member
  • ***
  • Posts: 52
    • Greenville, NC, Z8a
    • View Profile
Re: Poncirus hybrid crosses
« Reply #51 on: August 23, 2023, 02:29:27 PM »
Quote
Nothing against what was said above, if you want that much genetic variation in your population.  But there are already 4 mostly zygotic mandarin x Ponciris hybrids in use.  US 1279, 1281 and 1282 are more than 95% zygotic, and 852 is about 85% zygotic.  And Kumin has some F2 citranges that have survived 4 (or is it 5 now?)zone 6 winters.  And he has collected some citrimelos and such to bring into his population.  I think he is closer to success and will have an easier time than is being talked of here.
I am trying about the same way but I'm way behind him, in spite of his sharing his stock with me.  We are both in zone 6, but our climate and soil are different, and our time and space are different.
Also I am also working toward a hardy finger lime.  I didn't know that Australian citrus don't cross well with Ponciris.  However, at least one finger lime x Ponciris exists in Florida.  They aren't sharing it.  At least not with me.
I hope my saying this keeps others from trying to breed hardier citrus, and trying different methods, and working toward different goal.  I have been in touch with someone in Tennessee zone 7,  working on hardier kumquats via kumquat x Ponciris.  I think he will be successful in a few generations.
I wish success to all of us.  And have fun!

These are very good points. In hindsight, my post was probably too pessimistic/daunting. I certainly would never want to drive someone away from citrus breeding.

The two issues I see with those USDA rootstocks are the limited genetics and the even more limited availability. All three of them are derived from the same Poncirus parent and mostly the same mandarin parent as well, and to date, I haven't seen anyone actually offer them, at least to use plebs. I do plan to ask Stan McKenzie about them when I get around to visiting his nursery (had planned the trip on two occasions this summer, but scuttled those plans were, twice...).

US852, and the child seedling the name of which is escaping me at the moment, that I believe kumin also has, do seem like good options, though the same mild criticism still applies, limited genetics and even more limited availability.

Working with the more distant citruses, like the Aussie ones and kumquats, seems to me like it would be a bit riskier, since the wide genetic crosses could lead to trouble down the road (correct me if I'm wrong, but isn't Thomasville basically sterile, only able to clone itself? I feel like that kind of dead-end will turn up more often for those wide crosses). Not saying people shouldn't be doing it, not at all, I hope people are doing it, and I hope they succeed. I just strikes me as a riskier path.

Ilya11

  • Hero Member
  • *****
  • Posts: 916
    • France, Paris region, Vaux le Penil, middle of Northern z8
    • View Profile
Re: Poncirus hybrid crosses
« Reply #52 on: August 23, 2023, 04:27:24 PM »
Thomasville is fertile as a pollen partner.
Best regards,
                       Ilya

kumin

  • Hero Member
  • *****
  • Posts: 666
    • USA PA 6b
    • View Profile
Re: Poncirus hybrid crosses
« Reply #53 on: August 23, 2023, 04:27:51 PM »
Crossing Citrandarins with Citranges and Citrumelos should broaden the genetic base while conserving genes for palatability as well as cold hardiness. In the F generation there appears to already be a lowering of vigor in a percentage of the zygotic seedlings. In the Meyer Lemon x Conestoga 026 hybrids there appear to be fewer weak seedlings.
I would expect the depression of vigor to likely worsen in the F selfed generation.
Further trials should shed more light on this matter.

bussone

  • Member
  • ***
  • Posts: 159
    • Philadelphia, PA (7a)
    • View Profile
Re: Poncirus hybrid crosses
« Reply #54 on: August 23, 2023, 04:44:28 PM »
I didn't know that Australian citrus don't cross well with Ponciris.  However, at least one finger lime x Ponciris exists in Florida.  They aren't sharing it.  At least not with me.

I understand the Australians have one as well, but it's noted to struggle. Not so much that it dies, but it's not exactly happy about it, either.


1rainman

  • Sr. Member
  • ****
  • Posts: 460
    • Florida
    • View Profile
Re: Poncirus hybrid crosses
« Reply #55 on: August 27, 2023, 03:40:10 PM »
When you backcross to the 1/4 level fertility is restored pretty much other than a few low vigor seeds. It's like that with grapes muscadine x euviris. First generation hybrids have low fertility many have low vigor. It just needs crossed again.

But if you are dealing with three or more distant species that is more problems.

mikkel

  • Hero Member
  • *****
  • Posts: 531
    • Lueneburg, Germany Zone 7
    • View Profile
Re: Poncirus hybrid crosses
« Reply #56 on: August 27, 2023, 04:30:09 PM »
I understand the Australians have one as well, but it's noted to struggle. Not so much that it dies, but it's not exactly happy about it, either.

Microcitrus australasica x Poncirus hybrids also have been done in Florida by Ethan Nielsen. @ethane

The Microcitrus x Poncirus hybrids


Walt

  • Sr. Member
  • ****
  • Posts: 329
    • USA, Kansas, Kanopolis, zone 6
    • View Profile
Re: Poncirus hybrid crosses
« Reply #57 on: August 28, 2023, 12:44:35 PM »
1rainman.  That is what I thought likely.  Make the cross both directions, if I can.  Then backcross in both directions, if I can, and see what I get.  And go from there.

Mikkel. 

Curiousgardener23

  • Newbie
  • *
  • Posts: 5
    • United States, NorthEast Zone 6b
    • View Profile
Re: Poncirus hybrid crosses
« Reply #58 on: September 16, 2023, 02:52:10 PM »
Is there good information on favorable/interesting citrus traits in cultivated citrus that are dominant? This might be helpful when considering potential Poncirus hybrid outcomes. For example, given that many kumquat hybrids have thin edible skin, it might be the case that this trait is dominant. I'm sure this will depend on the genetics involved with the cross but it might be useful information when considering potential crosses. I think other trails that would be interesting to understand would be pigmentation (blood oranges) and sweetness. I know that sweetness (acidless) might be partially dominant when looking at the pummelo trait but recessive when looking at the orange trait (https://citrusgrowersv2.proboards.com/thread/728/inheritance-low-acidity). That being said, the low acid citrus genetics might be diverse so this might depend on the specific varieties in the cross.

 

SMF spam blocked by CleanTalk