Anyone here making intentional persimmon crosses? I am particularly interested in Kaki/Virginiana hybrids. Are these really hard to do and way out of scope for amateur breeders or simply that no one is really trying these?
What techniques were used in creating Rosseyanka and JT-02? Was it variations around mentor pollen and mentor grafting techniques or more esoteric methods?
I am currently trying mentor pollen technique with kiwis so technically are they much different for persimmon?
i don’t have persimmon’s. I am curious about your project though 
What method are you using to “sterilize” or “kill” the mentor pollen? How are you sure you got the right pollen to fertilize? instead of just an intact mentor pollen?
Could you Elaborate a bit on your technique/plan? Or did you alreaddy post about your kiwi project? Would be intresting for us to see i think 
I am thinking of using methyl alcohol to kill the compatible pollen.
The idea with kiwis is to create crosses of Hardy kiwi fruit with Chinensis. I’ve heard from the originator of the project(kiwibob) that there are often incompatibilities and so the idea was to use mentor pollen method.
The intact male Chinensis pollen is mixed with sterilized arguta pollen and applied to arguta female pollen. Nothing else to it.
It got me to thinking about persimmon as my female Virginiana persimmons ( H63A and H118) are budding out. I also see male flower buds on Zenji Maru, a Kaki. I am pretty sure crossing these would be exceptionally hard as there may be a ploidy issue as well. But fun to imagine what might be possible.
i never actually tried mentor pollen method. But came across it years ago. I could not find reliable data on % alcohol used. And timing. Since alcohol denatures proteins, i assume there is a fine line between not damaging the pollen enough, and damaging them so far they loose their (shape) stimulating effect. Most scientific articles mention radiation. I assume because that does less damage to the shape and possible stimulating effects. Than dissolving in alcohol does.
Either way it might be wise to record %alcohol used (pref new unopened bottel to be sure of %) and time soaked and probably temperature to.
And then pollinate a few flowers with just the mentor pollen. To see if you effectively killed them.
I also remember multiple freeze thaw cycles being used to create mentor pollen. Although i don’t know if those hardy kiwi’s also developed hardier pollen.
Anyway i’ll be looking with intrest at your project
Since i plan to try out these things in a year or 3 to.
I have a few male hybrids that I just let open pollinate my potted kakis. Most of the males are offspring of H-118 and Rosseyanka, which I like because of the potential for early ripening. But this year I also have a few hybrid male offsprings of Chinebuli flowering for the first time, which interests me for the potential of creating a non-astringent hybrid. I move the potted kakis to the desired male hybrid and hope for the best. I hope to be more deliberate in the future, but that’s all I’ve got time for at the moment.
@ramv Have you talked to Cliff England at England Orchard, KY? He’s a treasure trove of persimmon info.
Not yet. I will do this.
Its going to be
It is going to be very difficult to find information for this. First of all, I don’t believe this process to be repeatable since different pollen will act differently. I will simply dip in methanol and let it naturally evaporate.
If enough pollen is used, I imagine there will be atleast some pollen that is denatured but not damaged. Even if some of the pollen is hardly damaged, we will know when we grow them out if they are the right species within 2 years.
i would still use some of the “pure” mentor pollen to fertilize something than. To check if you killed them successfully. If you only kill 99% you will likely still get the mentor pollen as a parent. Since most hard to cross hybrids that need mentor pollen have low fertilization rates.
With kiwis atleast, it is pretty easy to tell if it is a pure arguta or has some chinensis – just by studying the leaf. It is a numbers game. There will be a few that are pure arguta and can be discarded.
Killing 100% vs 90% shouldnt make a huge difference in the end. You will grow them all out for 2 years atleast. Maybe most of the survivors are pure arguta but even a small number of actual crosses is a great thing.
I believe embryo rescue was also needed to get Rosseyanka to survive, and was the only cross of 22 attempts to make it. However, she seems to cross freely with either species now, so you may have better luck back crossing from Rosseyanka instead.
Even Luther Burbank failed to cross persimmons. Good luck!
I’m not far enough along to cross yet, but im growing a list partly for that puropse, one of the crosses I cant wait to make, is [NG(hybrid)xThor(american)] (a hardy hybrid with saijo-looking fruit and male flowers) with the hardiest large kaki Inchon, Steiermark, Great Wall, Miss Kim, and with Gora Goverla.
Maybe cross NGxthor with Prok too for a new male pollinator that has big early fruit from both parents and more american%, then cross the best selection of that which i can identify with these hardy kaki and goverla.
Also i hope to use JT-02 for a multi-cross as well, perhaps cross it and NGxthor, then cross that with all these hardy kaki, especially Miss Kim since its earlier and Inchon since its the hardiest kaki.
@ctduckhunter what you think?
One of my NGxThor grafts:
I’ve got some hybrid crosses of male Rosseyanka offsprings with Saijo, Rojo Brilliante, and Inchon (which is my most cold hardy kaki, although I don’t have Miss Kim, which may be just as cold hardy), as well as hybrids crossed with other hybrids. For the past few years, it’s been only about one third of the hybrid x hybrid crosses I’ve made that have produced seedlings that survive my zone 6 winters with no die back. So I’m not super confident I’ll get a cold hardy hybrid from my crosses back to pure kaki. But it’s a numbers game. Eventually someone will get a winner.
Very true!! The more numbers we do, the greater our chance of a super winner! We want an Inchon that is as hardy as JT-02 and as early as Miss Kim Great job I appreciate what you’re doing! I want to plant every seed my fruit make! we have so much to build off of that was not available to guys like us 50 years ago so this project has really advanced in a short time really so maybe we can build on what Mr Lehman, Mr Laverne have done and what Mr Cliff and Mr Don and others is doing and be part of the long term efforts!
It’d be really great if we can eventually get a non-astringent hybrid. It’d be kind of cool to have a bowl of those that you could snack on like big persimmon grapes.
Your grafts are looking great! I sure hope you and @SMC_zone6 make one that will work great for us in the future. I totally agree that a Hardy nonastringent hybrid would be accepted by all and make you the most wanted person on the trade forum. I hope to eventually try some of this, but this year has been rough for me. I am just spending all my time trying to keep things watered. I really struggle with the benchgrafts and pots. I have much better success with grafts on rootstock that has been in the ground for a year on persimmon n and 333 pear. Im switching gears next year, no more potted persimmons or pears after benchgrafting early. I will benchgraft when it warms up and these will all go into deep air prune beds.
@SMC_zone6 Good Thoughts! Yeah I have grafted Chinebuli for crossing to NGxThor and hope to plant out lots of seeds. That would be awesome if one could, well even if it just lost astringency super early just before softening and had a -18F or so hardiness and decent size!
@ctduckhunter Thanks! Sounds like a great plan! maybe me and you can spearpoint some good crosses like this! The potential is amazing!
