Interesting
Hello all,
I know the thread has not been active for awhile, but I’ve been reading through some of this and I wanted to throw out a question just in case somebody has insights.
Does anybody know whether JT-02 can be backcrossed to either DV or DK without embryo rescue? As I’ve understood it, F2 crosses do not require the technical heroics that F1 crosses do (between DV and DK). However, Cliff England posted something that makes me rethink this.
Cliff implies that JBT-06 is one of 8 crosses that Jerry Lehman sent to Japan for embryo rescue. He later says “JBT is Josephine X ( JT-02 )” (Redirecting...). If I am understanding this right, he seems to be saying that “JBT” stands for JT-02 backcrossed to Josephine. And apparently Jerry had to have this sent to Japan for embryo rescue?
I’m just trying to figure out if backcrosses with JT-02 would even be viable “in the backyard,” so to speak. Or would backcrosses require the same heroics that were required to create JT-02 in the first place.
Blessings,
Weston
Just a remark: Josephine and JT-02 are both females.
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Hmmm. Interesting.
Another interesting observation is the leaves of JBT-06 look more kaki-like than JT-02. They seem more glossy.
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@westonadams – Checking my notes, I see that I’ve recorded that JBT-02 is a back-cross of JT-02 with Taishu. I wouldn’t bet my life that my notes are correct. But I find it easy to believe that Cliff made some crosses. And maybe (?) JBT signified JT-02 Backcrossed to Taishu.
Edit: This is an error, corrected by Barkslip below.
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Thanks for the thoughts everybody. Has anyone confirmed any cases of JT-02 producing viable seeds?
JBT-06 is a 2014 open-pollinated chance of (3) Rosseyanka males that wind-pollinated JT-02.
There are no others within striking distance for JT-02 except these three males:
Rosseyanka male (-22 F hardy)
Costata x Rosseymale (-12 F hardy)
another Costata x Rosseymale (-12 hardy)
Costata is an American that was used in the breeding of male Rosseyxhybrids.
Best wishes,
B-slip
(I confirmed this information via email and via telephone to Cliff England)
All three males carry the hardiness gene/chromosomes.
JBT-06 is as hardy as JT-02 in every respect.
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So… are you talking about the Rosseyanka F2 male that David Lavergne bred ? IIRC it is essentially 3/4 D.virginiana - 1/4 D.kaki.
Costata, so far as I’m aware, is a Japanese D.kaki, not a D.virginiana.
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I thought I’d read that Costata is another name for Picudo - an astringent D. kaki.
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Ditto
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You guys are right. I assumed when I shouldn’t have. I was emailing with Clifford when I grouped all three into one question. He responded, one is a open-pollinated Rossey xvirginiana and the others are xCostata when I assummed costata was a virginiana I hadn’t ever heard of.
-12 F for a hybrid of Rosseyanka and a virginiana would not be -12 F. The other OP x Rossey with the pollen of a virginiana is a -22 hardy trees.
Thanks for bringing this up and clarifying. I appreciate it.
Dax
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Hi Dax,
Great! It is helpful to confirm that JBT-06 is indeed an offspring of JT-02.
Do you know if JBT-06 required embryo rescue? Or did Cliff just grow out the seeds in his “backyard”?
In other words, does JT-02 produce seeds that can be grown by you and I, or does it require laboratory equipment?
Weston
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Open-air pollination to JT-02 x (1 of 3 possibility maleRosseyanka hybrids).
1 is -12 hardy
1 is -12 hardy
1 is -22 hardy
all three carry the gene for cold-hardiness.
JTB-06 is every bit (the same) hardiness of JT-02. They’re planted right next to each other, btw. Only female flowers on both JT-02 and JTB-06. Both JT-02 & JTB-06 carrry the hardiness gene.
OK.
I haven’t yet been able to figure out if seeds from JT-02 require embryo rescue to be grown out. But that’s OK. Thanks for all the research you put into this!
Weston
Why is non astringent hybrid desired? What would it have that you couldnt get with a asian non astringent.
It’s air or hand-pollination. I thought you would “think” about what I was saying and learn.
only best regards
It’ll ripen on the tree and be hardy (possibly to as low as zone 5a) to 5b. And, be crunchy to eat off the tree.
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What’s been discussed (above) to a degree of certainty @westonadams is that once “the original” “embryo rescue” (JT-02) was lab produced, that pollen directly hit at the flowers of any or all hybrids of kaki x virginiana may be pollinated again by any pollen size grain. Kaki has one size pollen grain whereas virginiana has its’ own pollen grain size. The next step was to determine chromosome count where kaki has 60 chromosomes as does northen American persimmon continaing 60 chromosomes.
Southern American persimmon is 90-chromosomes and wasn’t a match for embryo-rescue . . . which too is good because its’ fruit is smaller and the trees are less cold hardy.
So the embryo thing was successful breaking the barrier uniting two different pollen sizes and the "subject’ was brought back to the United States.
Now we know that hybrids will accept pollen from virginiana or kaki. As to the 90-chromosome (x) hybrids, I don’t know much about that. There are a couple 90-chromosome American persimmon crosses at Jerry Lehman’s. Maybe it was one. Not more than two. And, they weren’t anything close to as good as the northern clade persimmons Jerry created mostly from James Claypool’s work which had a lot to do with the Northern American cultivar, ‘Early Golden’.
