The Tropical Fruit Forum

Temperate Fruit & Orchards => Temperate Fruit Discussion => Topic started by: TriangleJohn on April 15, 2015, 09:15:55 AM

Title: Cherimoya/Pawpaw hybrid
Post by: TriangleJohn on April 15, 2015, 09:15:55 AM
Some of you may recall that last year I had one branch of one of my Asimina triloba trees flower late in the summer. All four of my trees had flowered and fruited like normal but this one also had one branch flower again in August (and the flowers were on top of the branch and facing upward, which is odd). At the same time my Cherimoya tree was flowering in the greenhouse. I attempted to hand pollinate flowers on both trees. I had been told that Pawpaw needed an unrelated cross in order to fruit and since no other pawpaws were flowering at that time I assumed any fruit produced would be a result of the Cherimoya pollen. I had hoped that the Cherimoya would make fruit since it is indoors and protected from cold, thinking that a hybrid between them would not be winter hardy. Well the pawpaw did set fruit and I sowed the seeds and kept them isolated from any pawpaw seeds that I also sowed. Of the 6 seeds only two sprouted and one of them died almost immediately after sprouting. The lone survivor is doing well but growing slow (which is normal at this stage). I had hoped that the non-crossed pawpaw seeds would also sprout so that I could evaluate their leaves to determine if I indeed have a cross but so far none of them have emerged. I've been told that because their chromosome count is different that they more than likely did not cross and that this plant is a solid pawpaw. I've also been told that the local university can't do any sort of analysis on the tissues to determine if it is a cross. So the only thing I can do at this point is watch it grow and hope it appears different than a solid pawpaw.


(http://s13.postimg.cc/qxc60hpcz/DSCN0685.jpg) (http://postimg.cc/image/qxc60hpcz/)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: nullzero on April 15, 2015, 04:21:39 PM
Keep us updated, even if its most likely not a cherimoya cross its always interesting to watch a seedling progress.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: shaneatwell on April 15, 2015, 10:39:23 PM
Very cool. Good luck!

Are they graft compatible?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Marsbars on April 17, 2015, 03:07:21 AM
Did the supposed hybrid seeds look any different than  the pawpaw seeds?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: TriangleJohn on April 17, 2015, 10:20:19 AM
The fruit was smaller and the seeds were smaller and rounder. Still flat, but more of a perfect circle than the long stretched out shape of a pawpaw seed. The branch that bloomed twice last year is blooming and setting fruit now. I'll keep an eye on it to see if it reblooms again this year. The Cherimoya is started to wake up from its winter nap and it is developing flower buds. I need to really pay attention to it this year and try harder to hand pollinate it.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 18, 2018, 06:19:55 AM
Helo John, can you tell us, how this seedling did grow and if you can see any differences to a "normal" Paw Paw plant and to a "normal" Cherimoya plant? This would be very interesting for me also! Because I am also working on creating such an hybrid. I had stored Asimina triloba pollen in an refrigerator. At time my Chermioyas begin to bloom, and i am working to pollinate the flowers with Asimina pollen. Enclosed you will find a picture of my pollinating trial. One pollinated flower has fallen down but I think that I pollinated it too early - before female stage. Some more flowers will develop in the next days so I am hoping that I will get results. I will keep you informed about my success!
(https://i.postimg.cc/VJk02YYP/DSC08305.jpg) (https://postimg.cc/VJk02YYP)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 18, 2018, 04:40:08 PM
For informational purposes only:
Folks have tried crossing pawpaw with its tropical relatives before, if i'm not mistaken. Possibly as far back as Fairchild, Zimmerman...and possibly even Bill Whitman (I know he tried growing pawpaw but not sure about hybridizing).
Neal Peterson of eminent pawpaw fame has focused on Asimina inter-specific crosses and I believe had tried Annona crosses unsuccessfully prior to that (could be wrong on that).

To me the pawpaw is so unique and different from Annona species, i'm not sure what the goals of crossing would be. (legitimate question, not snark) :)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 19, 2018, 04:44:42 AM
Hello Triloba Tracker,

thanks for your comments and suggestions. I agree with you, there is not much chance of success, but who knows. I also researched a lot of literature and read testimonials on the subject, and everything I've read does not sound optimistic. But I mean, tasting is about studying. Certainly I have other individuals, live in another part of the world and certainly do not work in everything with the same parameters as all those who have already tried ... What motivates me is that I can already think of many things without much thought For example, the hybridization of Poncirus trifoliata with Citrus ichangensis, with Poncirus trifoliata as the parent plant, which was absolutely impossible according to literature research at the time .... it worked for me right away! Yes, the breeding goals you've been asking for, or the motivation to hybridize Annona and Asimina are the following - actually, I'd like to tweak some of Cherimoya's drawbacks:

- Cherimoya is subtropical, but not particularly cold tolerant. According to experience, light frosts are already causing massive damage to her. A hybrid could be a bit more cold-tolerant, but still suitable for warm climates (the pure Asimina develops poorly, it is poor in warm to hot regions)
- Cherimoya has a lot of seeds, but Paw Paw has few compared to the fruit mass, and there are also Paw Paw varieties that have very few seeds, taken as a parent ... .. A hybrid of both could be a kind of cranimoya with wizened cores
- The aroma of both parents is interesting in itself, in the mix, the Armoma could be a very special!
- Cherimoya has a relatively soft and sensitive skin, Asimina has a slightly more stable and pressure-sensitive consistency.
- Asimina has a clean separation of style and fear, even when ripe, she falls to the separation, and there is no hole in the fruit, which even when harvested to full maturity still allows a relatively long shelf life of the fruit. On the other hand, cherimoya dissolves from the stalk at full maturity, creating a crater-like wound in fear, from which mold and rot quickly spread, and spoil the fruit. A hybrid could have a smaller separation between style and fruit like cherimoya ....
- Pollination of Asimina-like flowers is easier for insects by the exposure of the inner flower parts, especially the female part, as pollination of the very closed female Cherimoya flower. A hybrid of both could have relatively exposed internal flower parts that are readily accessible to insects.
- last not least ... .The hybrid could be a cold-compatible pad for cherimoya, or you could ennoble these hybrids in addition to Asimina to grow as a hybrid in colder areas, or they as Zwischenveredlung (adapter) to then on to Cherimoya ennoble, also to culture in colder areas.

Maybe there are other arguments, but the mentioned ones motivate me anyway enough and enough to work on the hybrid. I've had it in my head for a long time, never done it, but after reading all that was written about it, I decided ....
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 19, 2018, 08:29:38 AM
I absolutely think you should do whatever you are driven to do! As we say, "there's a first time for everything."

Do you have mature Asimina triloba trees of your own? Or where are you getting your pollen?

I would quibble with a few of the things you mentioned about Asimina triloba:
1) If the fruit falls on its own, there will be a "scar" - a hole in the skin and slight indentation in the flesh. The fruit definitely does not have a clean separation like a mango or apple or pear. It can be cut at the peduncle to avoid this, but not if the fruit is in a cluster or if you are harvesting a lot of fruit.
2) The skin is actually usually quite thin and fragile. From the cherimoyas i've eaten, the cherimoya skin is much, much thicker and tougher than pawpaw
3) short shelf-life of pawpaw is considered one of its major drawbacks. I would say it's about the same as cherimoya, possibly worse.
4) i think a comparison of seed-to-flesh ratio of pawpaw and cherimoya would be interesting. Pawpaw is considered pretty "seedy" except for a few varieties particularly from Neal Peterson. Cherimoyas do have a lot of seeds, in a sense, but they are small and easily avoided. Pawpaw seeds are a little more annoying.

Take care!!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: starch on September 19, 2018, 09:44:09 AM

4) i think a comparison of seed-to-flesh ratio of pawpaw and cherimoya would be interesting. Pawpaw is considered pretty "seedy" except for a few varieties particularly from Neal Peterson. Cherimoyas do have a lot of seeds, in a sense, but they are small and easily avoided. Pawpaw seeds are a little more annoying.

Take care!!

It's funny because it is all relative. After eating lots of sugar apples that have *tons* of seeds, I don't think cherimoyas are all that seedy! It all depends on your basis of view :)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 19, 2018, 12:10:27 PM

4) i think a comparison of seed-to-flesh ratio of pawpaw and cherimoya would be interesting. Pawpaw is considered pretty "seedy" except for a few varieties particularly from Neal Peterson. Cherimoyas do have a lot of seeds, in a sense, but they are small and easily avoided. Pawpaw seeds are a little more annoying.

Take care!!

It's funny because it is all relative. After eating lots of sugar apples that have *tons* of seeds, I don't think cherimoyas are all that seedy! It all depends on your basis of view :)

Agree!
That’s why seed to weight/flesh ratios would be interesting to compare.
For example Neal Peterson’s Susquehanna pawpaw he reports only 3% seed by total weight. That’s considered very low (good).
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 19, 2018, 05:05:41 PM
@all: Thanks for your replies and thoughts!

@Triloba Tracker
to 1) I agree with you that with Paw Paw, when it is ripe from the tree, a small scar is formed, but for a long time there is no wound as big as that of the Cherimoya, when the fruit is fully ripe and trapped by gravity, the stem becomes full Fruit marc ripped from the middle of the fruit when it falls from the tree. Here are a few photos that show how small the wound is when Paw Paws fall from the tree. There is nothing left behind, and the fear has a small wound that dries quickly, and nothing bad at the fruit happens in the next days. while at same time a Chermioya fruit will begin rottenn and smudges at her great wound and the fruit soon spoils ....all happens after it falls fully ripe from the tree. Of course, you can trim them immature on the stem, but fruits ripened on the tree are more valuable in terms of better flavor.
Regarding 2) The Paw Paw strains I have and the Cherimoya strains that I have are the other way round, it is quite a skin resistant to pressure and injury to Paw Paw and quite sensitive and sensitive to the skin of Cherimoya , It may be that there are varietal differences regarding the stability of the skin in both Paw Paw and Cherimoya.
to 3) I have experienced that Paw Paws harder if they fall from tree like Cherimoyas, probably because of 1)
to 4) Definitely there are some - and also non-Petersen - varieties, which fruits show little number of seeds and much flesch. The best I have is Prima 1216, an Italien breed. As a rule, the fruit is no longer like 6-7 seeds, and the fruits are also huge!
In addition, Paw Paw quickly finished when you cut the fruits along, you pull out the manageable number of cores, as they are usually all sees and finds, and can spoon out the rest. At Cherimoya, the core quest does not stop until the fruit is finished .... it's really annoying! A hybrid of both might have a smaller number of nuclei like Chermioaya.
(https://i.postimg.cc/N5RZMRVh/DSC08370.jpg) (https://postimg.cc/N5RZMRVh)

(https://i.postimg.cc/TyN4S0yb/DSC08371.jpg) (https://postimg.cc/TyN4S0yb)

(https://i.postimg.cc/fk9r2xM3/DSC08372.jpg) (https://postimg.cc/fk9r2xM3)

(https://i.postimg.cc/K1Zp8wBL/DSC08387.jpg) (https://postimg.cc/K1Zp8wBL)

(https://i.postimg.cc/QF049mJz/DSC08390.jpg) (https://postimg.cc/QF049mJz)

(https://i.postimg.cc/QF049mJz/DSC08390.jpg) (https://postimg.cc/QF049mJz)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 19, 2018, 05:29:27 PM
I agree and all excellent points!
Great pictures.

How long have you been growing pawpaw? Would like to hear more about your trees, etc
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 19, 2018, 05:34:52 PM
Hi, to your question - for 25 years I am growing Paw Paws now! Yes, we can Keep in contact of course!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 19, 2018, 06:15:24 PM
That's awesome!

yes feel free to send me a message.. also it might be nice to hear about your pawpaws, in general, over on the "asiminaholics anonymous" thread...
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triphal on September 21, 2018, 08:26:16 PM
Since September 5, I have been picking and plucking over hundred (100) fruits a day average. Only about 30 left in the trees now. I have planted 3 grafted trees 'clumped or packed within 12 feet! One each of Pennsylvania, Susquehanna and Sunflower about 8 or 9 years ago. Last year we had more fruits,so didn't expect much this year.
The seeds are very light but  bulky. And Neal Peterson's " seeds are 3% of the fruit" is unintentionally misleading. By volume I feel seed to pulp ratio is about 55 to 45. Most (over 95%) of our harvest was distributed to friends. If we mulch generously and keep the under brush heavy, fruits will have less injury. We are about 4 to 5 miles away from the closest river. But a stream connecting that river is only half a mile away from our property. Our well is about 200 feet deep and the water table is about 125'. We had a dozen of almost 6" long fruits! But in general fruits of variable sizes from one and a half inches(very few) to 5". They are all delicious.
Early yellowish change in the color and fullness at the stalk  and sometimes small insects floating around and of course the smell are signs to harvest. But the trees are about 35 feet tall and it is hard to harvest most of them by hand without using a ladder. As soon as you harvest keep it in the refrigerator in the garage.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 22, 2018, 05:05:31 PM
Thank you for sharing your experiences here with us. I can confirm much of what you have done. The repeatedly stated small appearing ratio of the seeds to the rest of the fruit is actually misleading! The weight of the seeds is relative to their volume very light and much lighter than the pulp of the fruit. I can confirm that about 50%, with some varieties it is a little better. The best variety is Prima 1216, an Italian selection, it has not only a better ratio of semen volume to fruit volume, but few kernels, at most only 5-7 kernels per fruit, which are quickly found and removed. The kernels are slightly larger than at other paw paw varieties, but as I said, they are quickly found and removed due to the low number of pieces! So the food of the fruit is not so tedious and it makes more joy. To taste, I find all varieties good.

Interesting what you wrote to determine the fruit ripeness. I have not noticed the colouration of the string in the direction of yellow, but now that you've written it, I notice ...... you're right! Of course, the smell is an unmistakable sign, and those that grow close to the ground, where I carefully test whether they detach themselves from the stalk, because I like them most when they fall fully ripe from the tree. Only if they actually fall, and land on the ground, then they can be damaged, and worse, come with me from time to time also snails and eat them. For many years now, I have been attaching small nets to the respective branch for particularly large and beautiful fruits, which actually come as waste from fruits and vegetables from the supermarket. The ripe fruit then falls into the net and remains undamaged and unreachable for Schnecken! I attach a photo to it. This year, for a test, I stretched a net under a tree into which the ripe fruit could fall. It has proven itself. It is less work and if you check it several times a day, it does not or rarely happens that one fruit falls on another fruit. Of course, the net has to be fastened in several places and supported in the free areas more than soft. Attached also a photo of the net that has just caught a fruit.

This year, I harvested every few fruits and passed them on ... I usually weighed between 80 and 170 grams. Some (few) were smaller, some were a bit bigger. Since we had a hot, dry summer, about 50% of the fruit fell off in July and partly in August, the kernels were still light, the flesh was not finished yet, you could not eat it ... but it still existed still enough ripe fruit now in September. I've been harvesting Paw Paws for three weeks, but now all the fruit has been harvested. I have also distributed some in the circle of acquaintances. Also some that you have not known. Almost everyone is excited. Only one said he did not taste it, it's the consistency of the flesh that's not his case. But he also does not like cherimoyas .... I'll sit with you for the storage of the fruits, a cool place helps to extend the shelf life, but still, I like the most ripe ones from the tree when the shell is getting dark , and then the taste changes, I think they are not that great anymore, but they are eaten anyway!
(https://i.postimg.cc/r0X6k6Hg/Fruit_not_fallen.jpg) (https://postimg.cc/r0X6k6Hg)

(https://i.postimg.cc/F7WHQRVZ/Fruit_in_Net.jpg) (https://postimg.cc/F7WHQRVZ)

(https://i.postimg.cc/qN64VGRJ/Fruit_in_net_2.jpg) (https://postimg.cc/qN64VGRJ)

(https://i.postimg.cc/rRp2h13L/Fallen_Fruits.jpg) (https://postimg.cc/rRp2h13L)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on October 12, 2018, 04:53:30 PM
Update: One of the Cherimoya  flowers which I have pollinated with Asimina pollen set fruit. I am not to 100% sure that it is only pollinated with Asimina pollen, it could also be pollinated with pollen of Cherimoya. Nevertheless.... the Asimina pollen has been the first who could have pollinated the flower....Now we will wait - hoping that the fruit will get ripe add not fall down unripe.

And now I am collecting some Chermimoya pollen to pollinate some Asimina flowers next spring;-) Because Imy Cherimoya plant is small and have only few flowers I try to collect any pollen possible with a little plastic box which I have fastened below the flower a short time bevor switching into the male mode.

(https://i.postimg.cc/Vd438n9Z/Young-Fruit.jpg) (https://postimages.org/)

(https://i.postimg.cc/qhTTR0N1/Pollen-collecting-with-cap.jpg) (https://postimages.org/)

(https://i.postimg.cc/ZWvtx03f/Pollen-fallen-in-cap.jpg) (https://postimages.org/)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: KarenRei on October 12, 2018, 08:11:44 PM
And now I am collecting some Chermimoya pollen to pollinate some Asimina flowers next spring;-)

You expect it to be viable for that long?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on October 14, 2018, 03:37:47 PM
@Karen: Yes, I do. Commercial growers of Cherimoya are soring the pollen of Cherimoya in the refrigerator to be able to pollinate flowers sometime later. I will kepp the pollen frozen by -25 °F until next spring for pollinating Asimina flowers with it.
Maybe I will make a test next year for visbility.....and take some of this pollen for seeing the result when pollinating Cherimoya flowers with it....
Title: Re: Cherimoya/Pawpaw hybrid
Post by: TriangleJohn on November 14, 2018, 07:58:00 PM
usirius - do you get any natural pollination on cherimoya? I have to hand pollinate my flowers, the local insects ignore them.

I still have two of the possible hybrids. They have been very slow growing which is typical for pawpaws under my care. I have had them outside in pots this fall but my drag them into the greenhouse to save them from harsh winter weather. The leaves look just like pawpaw leaves so I doubt they are hybrids.

For years I collected and sowed seeds for my pawpaws but now I simply wait for a very rainy day in the middle of the winter after the suckers around the parent trees have gone dormant and I simply pull the suckers out of the ground. They snap off of the mother plant's root with a sort of an elbow shape and often one tiny fragile root. I pot them up with standard potting soil and leave in a sheltered area. They sprout in the spring and usually start growing very fast. I plant them in the ground after one full year in a pot (to get maximum root growth). Some of these transplants even flower and fruit while still very small. This method is much better than seed growing for me.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on November 15, 2018, 08:12:30 AM
That’s really interesting, TJ. Goes against everything I’ve read about near-impossibility of transplanting or especially starting from a sucker.
Of course, that means precisely nothing! There are few absolutes in this business . Obviously it’s working for you!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on November 27, 2018, 03:22:24 AM
@ TT/TJ: Most of my PawPaws are breeded varieties. Only one tree produces suckers. Only one has started last year to make root shoots. I let them grow first, they are still small. Usually I either buy grafted plants or I even refine sorts that are not or hardly available for sale. For example, I have a variety that is self-pollinating, but is not both the Prima1216 variety and the Sunflower variety. Refining is a bit tricky, you have to refine dormant material to driving documents at the right time. With a bit of luck, that will work. Rooting of vines, which is not a problem with other fruit trees such as citrus, apples, berry bushes and so on, I have not made at Paw Paws yet. -  @ TJ: To your question, whether pollinating insects Paw Paws with me: Once this actually worked without any help from me, but usually I have to dust by hand to get fruit. For the PawPaws this took a while until the insects learned it here, the Paw Paw is not homey here. But now they know it, and have probably "inherited" the learned knowledge to their offspring, every year more and more flies, small insects and different beetles such as rose beetle or wood beetle come. - The mention of the mentioned me asimina pollen pollinated flower blossom has formed a fruiting body, which is still on the plant, see attached picture, it is now about the size of a cherry. 12 hours later, after pollination with Asimina pollen, I dusted up with cherimoya pollen ... to make sure that the fruit does not fall off ... so some kernels could actually have Asimina as father ... it remains exciting. In the spring I will pollinate in turn, frozen cherimoya pollen on asimina flowers. I will report.

(https://i.postimg.cc/KKL5xMrz/Cherimoya-x-Paw-Paw.jpg) (https://postimg.cc/KKL5xMrz)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Draak on March 22, 2019, 01:28:49 AM
This is really exciting! I have 4 pawpaws, but another annona fruits really struggle here. I'm really hoping you get some good results :).
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on April 01, 2019, 09:23:30 PM
In the early 1990's, Mr. Crafton Clift and I, both of whom had been working for years as plant breeders, repeatedly over-night-mailed pollen of Asimna triloba and Annona species to each other, and used it immediately when it arrived.  For this experiment, he was in his hometown, Newburn, Tennessee, with plenty of large Pawpaw trees, and I was in Boynton Beach, working with the many species and varieties available in the breeding collection at Zill's. 

Although most of this pollen was used when it was less than 24 hours old, it was definitely not fresh, and not refrigerated or prepared in any way, just enveloped as it was.

All cross-genera pollinated flowers  were quickly rejected. Dropped.  Hundreds of them.

One cannot prove a negative, but pollen mailed that way is probably going to be a waste.  Fresh on the same property?  Who knows!  We were never so blessed.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 17, 2019, 06:15:12 AM
Thank you for sharing your interesting experiences by using mailed pollen. I cannot imagine that normally stored Asimina or Cherimoya pollen will survive for more than two or three days and than still be able to pollinate flowers. I pollinated a cherimoya flower with asimina pollen stored in a freidge. I hope that the fruit of the result does include hybridisized seeds. The fruit has growed to a big fruit in the meantime, I will upload a picture later. From the flowering Cherimoya I stored some pollen frozen in my fridge. In some days my Asiminia plants (I will take the varieties Sunflower or Prima1216 ) will start to bloom and than I will pollinate some flower with Cherimoya pollen and mark them. I give updates as soon as there are any news.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on April 17, 2019, 12:52:16 PM
Thank you for sharing your interesting experiences by using mailed pollen. I cannot imagine that normally stored Asimina or Cherimoya pollen will survive for more than two or three days and than still be able to pollinate flowers. I pollinated a cherimoya flower with asimina pollen stored in a freidge. I hope that the fruit of the result does include hybridisized seeds. The fruit has growed to a big fruit in the meantime, I will upload a picture later. From the flowering Cherimoya I stored some pollen frozen in my fridge. In some days my Asiminia plants (I will take the varieties Sunflower or Prima1216 ) will start to bloom and than I will pollinate some flower with Cherimoya pollen and mark them. I give updates as soon as there are any news.

Awesome - good luck and can't wait to see the pictures.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 19, 2019, 03:36:12 PM
Enclosed you will find some actual pictures from my trials of hybridization of Paw Paw and Cherimoya:

- Fruit of Cherimoya - Flower has been pollinated with Paw Paw pollen - hoping that noCherimoya pollen has also pollinated the flower
- Flowering Paw Paws - Varieties Mango, Sunflower and Prima1216 - which today have been pollinated with frozen stored Cherimoya pollen - pollinated flowers are wrapped in a thread as marking method
- Protection net to make sure that hopefully no insect pollinates the pollinated flowers

(https://i.postimg.cc/grm2Jqwr/Chrimoya-pollinated-w-Asiminia-pollen.jpg) (https://postimg.cc/grm2Jqwr)

(https://i.postimg.cc/8s4PrJW4/Mango-cherimoya-pollinated.jpg) (https://postimg.cc/8s4PrJW4)

(https://i.postimg.cc/21bzJ0t9/Prima-1216-Flowers.jpg) (https://postimg.cc/21bzJ0t9)

(https://i.postimg.cc/sMkVRpdj/Protection.jpg) (https://postimg.cc/sMkVRpdj)

(https://i.postimg.cc/Ln09NcxZ/Sunflower-chrimoya-pollinated.jpg) (https://postimg.cc/Ln09NcxZ)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on April 19, 2019, 05:10:52 PM
Wow that’s really cool what you have going there!

Have you tried putting bags or mesh around the individual flowers?
I’ve never done controlled crosses like this but always thought if I did I would bag target female flowers before they even open, remove bag just for me to pollinate, and immediately bag it again until fruit begins to form.
I have organza (type of fabric) bags from papermart.com
Title: Re: Cherimoya/Pawpaw hybrid
Post by: pvaldes on April 19, 2019, 08:59:23 PM
How do you deal with the frost in Germany @usirius? Is not too cold there for Cherimoya survival or fruiting?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 20, 2019, 04:03:21 PM
@ Triloba Tracker:

I covered not evry single flowers with a bag due to I do not have such bags and due this is more work and time intensive. I covered some twogs together with a net. The insects which here visits the flower are considerably smaller than the size of the holes of the net.

My strategy of pollinating Paw Paw with Cherimoya Pollen this year is the follwing:

- use several Varieties of Paw Paw to increase the likelihood of success
- take also Paw Paw verieties which are self fertile - they seem for me having less probles with other pollen
- take not the first flowers and not the last oness. Be between, but more tot the beginning wher enot so much Paw Paw Pollen is available
- pollinate the same flower several times - each time with freshly unfrozen pollen - which I have frozen in protions in my fridge
- mark pollinated flowers
- avoid other pollination by protection

I think tomorrow I will be ready with pollinating Paw Paw flowers in this sprng...because I am not having very much Chermioya pollen. I have pollinated in total a little bit more than 20 flowers. And but if only one fruit crossed with Cherimoya Pollen will develop to full maturity I would be happy!

@ pvaldes:

In Germany it is only possible to grow Cherimoya in plein air during spring until autumn where it flowers. From autmn to spring  it need to be protected from freees. Perfect would be a green house - or a sunny place in a house and at temperatures around 15°C . According to my Long year experiences fruits develop and get ripe by treating the plants as described. And they are as tasty as those grown in warm climates.

Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 21, 2019, 04:32:49 PM
Today the fruit of Cherimoya has fallen down after fully ripened - the flower before this fruti has developped has been pollinated in last autumn by cool (not frozen) stored Asiminia pollen. Now let's see what happened or not...I first will enjoy teating the fruit of course and take some photos after opening it. Enclosed you will find some photo from the still unopened fully mature fruit after falling down.
(https://i.postimg.cc/9zvQ0Vcn/DSC00353.jpg) (https://postimg.cc/9zvQ0Vcn)

(https://i.postimg.cc/JszvWD9V/DSC00354.jpg) (https://postimg.cc/JszvWD9V)

(https://i.postimg.cc/23vfHWf0/DSC00355.jpg) (https://postimg.cc/23vfHWf0)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 21, 2019, 04:41:27 PM
Today I was able to take photosn which show how effective this simple form of protection - a fine-meshed net - can be in protecting flowers from unwanted foreign pollination for hybridisation trials! -The two picture show a rose beetle that likes to eat pollen from pollen containing flowers like the Paw Paw flowers. Before I took those two pictures, the beetle flew around the net for about 1 minute! So he wanted to get to the flowers that are protected in this net!
(https://i.postimg.cc/9rs21BDg/DSC00358.jpg) (https://postimg.cc/9rs21BDg)

(https://i.postimg.cc/2LVp7qrf/DSC00359.jpg) (https://postimg.cc/2LVp7qrf)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 25, 2019, 05:06:56 PM
Now it is time to inform you what I have found in t he inside of the frut where the flower has been  pollinated with Paw Paw Pollen.
At first I noticed after the oven that it contained relatively much flesh and relatively few seeds. It was very pleasant to eat! And the taste like Ananas with some Lemon aroma. Only 20 seeds I could find in this big fruit, that's almost Paw-Paw level! The seeds have an unusually small size. The weight of the 20 grains has been 4,5 grams. They are smaller than Paw Paw kernels and smaller than Cherimoya kernels. But they seemed to be developed. The question is how to proceed now. Stratify? Or rather not, because Paw Paw has genes in it. It remains exciting! The first two PawPaw flowers pollinated with Cherimoya pollen have fallen off today, but there are still a lot of them hanging around. We'll see how the hybridization story goes on, it's not over for me yet!

(https://i.postimg.cc/KkBcj1LD/DSC00564.jpg) (https://postimg.cc/KkBcj1LD)

(https://i.postimg.cc/yWh0xPFt/DSC00582.jpg) (https://postimg.cc/yWh0xPFt)

(https://i.postimg.cc/345DJ4W3/DSC00639.jpg) (https://postimg.cc/345DJ4W3)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: SeaWalnut on April 25, 2019, 05:18:27 PM
To avoid stratification you could try gibberellic acid on them .Various concentrations and not on all the seeds ,keep some to sow like annona.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on April 26, 2019, 01:43:40 AM
SeaWalnut

Thank you for thiis useful hint, sounds well. I thought to treat some of them in a medium like manner - by regarding sawing of Cherimoya and Paw Paw seeds..
, I will try to store them two or three weeks at a cool er place - maybe 10 °C and than let them gow at a warm place.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: NickTheNZgrower on May 01, 2019, 12:35:22 AM
This is an amazing experiment and I'm following with interest. No one, as far as I know, has got as far as you, to have seeds now from a Cherimoya pollinated with pawpaw. The seeds actually look like a mix of cherimoya and pawpaw seeds so this looks really promising... Wow. Be sure to update us once the seedlings emerge. I'd try a few stratified and the rest planted like cherimoya :)

Nick
Title: Re: Cherimoya/Pawpaw hybrid
Post by: SoCal2warm on May 07, 2019, 02:12:15 PM
Some research I was able to dig up:

George A. Zimmerman undertook an 18-year project to breed pawpaw, attempting to produce intergeneric hybrids by crossing Sugar Apple (Annona squamosa) and atemoya (A. squamosa x A. reticulata) with Pawpaw (Asimina triloba). He was unsuccessful. But he did successfully create interspecific
hybrids by crossing Asimina obovata, A. longifolia, and Asimina reticulata with Asimina tribola. The A. triloba x A. obovata hybrids appeared fertile.
Unfortunately, Zimmerman died in 1941 before his other crosses matured.

Pawpaw Variety Development: A History and Future Prospects, R. Neal Peterson,
Horttechnology, July-September 2003
Title: Re: Cherimoya/Pawpaw hybrid
Post by: SeaWalnut on May 07, 2019, 02:30:10 PM
Most otther Asimina species are verry little shrubs except A Tetramera from what i remember and are highly endangered species.They are also edible but reports say they dont taste as good as A Triloba.In USA there is a woman that dedicated her time in conservating those endangered Asimina species.http://www.indefenseofplants.com/blog/2018/3/13/the-other-pawpaws (http://www.indefenseofplants.com/blog/2018/3/13/the-other-pawpaws) Here is a link with an interview with that lady about the otther Asimina species she is trying to protect. http://www.thesurvivalgardener.com/floridas-amazing-native-pawpaws/ (http://www.thesurvivalgardener.com/floridas-amazing-native-pawpaws/)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on May 07, 2019, 02:58:33 PM
Most otther Asimina species are verry little shrubs except A Tetramera from what i remember and are highly endangered species.They are also edible but reports say they dont taste as good as A Triloba.In USA there is a woman that dedicated her time in conservating those endangered Asimina species.http://www.indefenseofplants.com/blog/2018/3/13/the-other-pawpaws (http://www.indefenseofplants.com/blog/2018/3/13/the-other-pawpaws) Here is a link with an interview with that lady about the otther Asimina species she is trying to protect. http://www.thesurvivalgardener.com/floridas-amazing-native-pawpaws/ (http://www.thesurvivalgardener.com/floridas-amazing-native-pawpaws/)

Very interesting - thank you for sharing! I have not really had any interest in other Asimina species. I have seen them in the Florida panhandle quite readily (e.g. Watercolor/Seaside), however, and even have found fruit. Not sure which species these were.

I love the picture of the massive taproot. Also interesting to hear that these other pawpaws have the same strong taproot and do not like the roots disturbed.

I have bare-rooted container grown pawpaws and it didn't kill them but it did seem to slow them down. However, I just planted a container-grown tree in the ground; the potting mix all completely fell away, so it was basically bare root. But it is growing vigorously. (KSU Chappell)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on May 07, 2019, 03:58:06 PM
Asimina tetramera is a small shrub;  the several dozen that I have seen were all under 4-feet tall.

Asimina parviflora and Asimina obovata can be small trees, over 10-feet tall.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on May 08, 2019, 06:17:54 AM
SeaWalnut, Guanabanus, So2Calwarm: Thanks a lot for sharing those interesting information. To work on cross and hybridisizing experminets with different representants of the Paw Paw family seem to be interesting! I could imagine that the geometriy and colour of the flower can be a sign for the success in cross trials. For example A. triloba and A. parviflora show similarlities in their flowers - and has been crossed with success....

 Nevertheless I am going on in working on my Asimina hybrids....from for about 20 pollinated flowers still 10 are alive. But I am not 100% sure that those flowers have also been pollinated with Paw Paw pollen by very small insects like ants or emmets....because the holes in the net are wide enough for such insects and I have seen ants in flowers of other Paw Paw trees I have. But what I can say is that the Cherimoya Pollen has been the first on the stamps of the pollinated flowers ;-) We will see what happens.

The seeds of the Cherimoya fruit which flower has been pollinated with Paw Paw Pollen some months ago are already put and stored in some moisty soil for I would say 4 weeks and for about 5°C, I think not too cold for Cherimoya and cold enough for stratification if needed.... 

All: Do you think, that growing of such hybridisized seeds can work when treated in such manner?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Ilya11 on May 09, 2019, 03:13:48 PM
Annona and Asimina have very similar genome size (1.7pg) but different chromosome numbers: 2x7 for Annona and 2x8  for Asimina.
It is probably worth to produce tetraploids in both species by chromosome doubling and than to  cross them.
Like this the fertility barrier has been broken in many other agriculturally important plants.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on May 21, 2019, 01:47:40 PM
@ Ilya11
 
Thank you for explanation of the scientific / genetic correlation and background. Well, this sounds logical that this may have a significant influence on the probability of pollination / hybridization success.

 
@All
I will not give up so quickly! One of my well experienced life mottos is “tasting is about studying”

Enclosed you will find some pictures of my actual Asiminia-Cherimoya-hybrid trials.

From about more than 20 pollinated flowers there are still some remaining an seem to grow to a fruit. As already noted some time before  I have marked the pollinated flowers with a tie.

First Picture: With Cherimoya Pollen pollinated flower of variety 'Mano' - still alive
Second Picture: With Cherimoya Pollen pollinated flower of variety 'Sunflower' - still alive (also two other omes)
Thir Picture: With Cherimoya Pollen pollinated flower of variety 'Prima1216' - dead (there are also many other dead pollinated flowers - all varieties)
Fourth Pictur:  With Cherimoya Pollen pollinated flower of variety 'Prima1216' - still alive
Fifth Picture:With Cherimoya Pollen pollinated flower of variety 'Prima1216' - still alive (and three other ones)
Sixth Picture: Do you have any idea?  ;-)

We will see what will happen the next weeks and months.
(https://i.postimg.cc/LhjR8d8f/DSC06192.jpg) (https://postimg.cc/LhjR8d8f)

(https://i.postimg.cc/PPmq9pwg/DSC06195.jpg) (https://postimg.cc/PPmq9pwg)

(https://i.postimg.cc/hh8Wq921/DSC06198.jpg) (https://postimg.cc/hh8Wq921)

(https://i.postimg.cc/qzQPNpVt/DSC06199.jpg) (https://postimg.cc/qzQPNpVt)

(https://i.postimg.cc/tYCXSS9x/DSC06200.jpg) (https://postimg.cc/tYCXSS9x)

(https://i.postimg.cc/dL1Ymh9R/DSC06201.jpg) (https://postimg.cc/dL1Ymh9R)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Ilya11 on May 21, 2019, 02:05:44 PM
Actually, do somebody know if there are  tetraploids of Asimina?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on May 21, 2019, 03:00:28 PM
A paper published in Australia in 2014, indicated a lack of success, up till then, in producing tetraploids of atemoyas [called "custard-apples" over there].  I haven't seen any updates.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Ilya11 on May 22, 2019, 04:26:18 AM
It seems that spontaneous triploids and  tetraploids are observed in cherimolaX atemoya backcrosses.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/ (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/)

Triploids seedlings  also occur in Asimina in areas with high temperature fluctuation during flowering
https://www.jstor.org/stable/2481881?seq=1#page_scan_tab_contents (https://www.jstor.org/stable/2481881?seq=1#page_scan_tab_contents)

That  means that a sufficient number of unreduced diploid pollen grains is produced in Asimina and can be used to pollinate flowers of cherimolaX atemoya that  has a natural tendency to produce fertile unreduced female gametes.
This may result in tetraploid and probably fertile AnonaXAsimina plants.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on May 22, 2019, 11:39:20 AM
It seems that spontaneous triploids and  tetraploids are observed in cherimolaX atemoya backcrosses.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/ (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/)

Triploids seedlings  also occur in Asimina in areas with high temperature fluctuation during flowering
https://www.jstor.org/stable/2481881?seq=1#page_scan_tab_contents (https://www.jstor.org/stable/2481881?seq=1#page_scan_tab_contents)

That  means that a sufficient number of unreduced diploid pollen grains is produced in Asimina and can be used to pollinate flowers of cherimolaX atemoya that  has a natural tendency to produce fertile unreduced female gametes.
This may result in tetraploid and probably fertile AnonaXAsimina plants.

That C i made in college genetics is coming back to haunt me.....  ???
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on May 22, 2019, 03:48:06 PM
Thank you, Ilya11, for finding that very recent paper!

I am surprised at the implication that we have been producing triploids and tetraploides all along, simply by interspecific breeding. 

None of the interspecific hybrids that I produced were seedless.  Quite a few, however, were fruitless.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on May 22, 2019, 04:39:54 PM
So, fill in the blanks for this Mendelian flunky....

What does all this tell us about the possible pathway to, say, a seedless pawpaw? Someone needs to start crossing Asimina triloba with Annona cherimola x atemoya backcrossed progeny?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Ilya11 on May 22, 2019, 05:06:37 PM
Diploid Asimina/Anona hybrids that Usirius is trying to produce will most probably be non fertile since two parents have different chromosome numbers.
But crossing the combination of two tetraploids will give a tetraploid hybrid with balanced chromosome number. This could be done either by a generation of tetraploid Asimina and Anona by colchicine  or oryzalin treatment and than crossing such plants, or by pollination of hybrid  atemoyas with an excess of Asimina pollen.

Triloba Tracker,
I do not think that triploid asimina will be very fertile like triploid citrus varieties.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on June 30, 2019, 12:31:23 AM
Also thanks from my side for this interesting paper and thoughts for possible future crossing work!

Back to the thread here....I will give you a short update about my crossing trials of Paw Paw togehter with Cherimoya.

- From my spring crossings of Asiminia triloba flowers with Cherimoya pollen most flowers died after Setting fruit. Also many other "normally" Asimina flowers died - may be the wheather (cold period with some night freezes after flowering) may be the root cause. One fruit of a pollinated flower is still alive...

- The seeds of the fruit harvested in spring as result of last year done cross Chermioya flower with Asimina triloba pollen now are germinating - see 2 photos enclosed. One seed seem to germinate as a pair of twin plants...I will keep you informed concerning growth and viewable interspecific signs or properties...

- My mother plants of Cherimoya starts to flower again (see photo enclosed)  - as early as never before - two monts later than Asimina triloba ended flowering....so I will be able to pollinate this tame with more fresh pollen whch I have stored frozen in my fridge - spollen of everal varieties of Asimina I will try to use. I will Keep you informed.

Now I am looking Forward concerning new pollinating Trials and growing of the Young seedlings. And with some luck I will harvest a fruit of Asiminia in autumn wihich flower has been pollinated with Cherimoya pollen.

So there are still many Options for success..we have to wait still some time and than we will see what has happened ;-)

(https://i.postimg.cc/JD76FGD8/DSC06687.jpg) (https://postimg.cc/JD76FGD8)

(https://i.postimg.cc/G9HTjd7s/DSC06688.jpg) (https://postimg.cc/G9HTjd7s)

(https://i.postimg.cc/HV1W7gfm/DSC06690.jpg) (https://postimg.cc/HV1W7gfm)

Title: Re: Cherimoya/Pawpaw hybrid
Post by: NickTheNZgrower on July 09, 2019, 04:19:01 AM
This all looks great, thanks for the update. I'm really glad the seeds are germinating. Were these ones stratified?

Looking forward to seeing the seedlings once they have more size.

Nick
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on July 09, 2019, 12:05:13 PM
@ Nick,

the seeds I have treated for stratification as I proposed some time ago - I used only coldness.

In detail I did the following steps:

- After opening the fruit and cleaning the seeds from the fruit flesh I dryed the seeds for a half day at 15°C
-  Than I layed the seeds in slightly moisty soil
-  After this I stored them some days at  temperatures for about 15°C
-  Next step I put the seeds into a fridge and stored them there for 4 weeks at about 5°C
-  Now I put them into plein air - summer time -  temperatures 24-33 °X - first germinating occured after about three weeks waiting time

Enlosed there are some new pictures of the seedlings. For me the leafes looks more similar to Cherimoya leafes. One seedling still is connected with the shell of one of the very special shaped grains - this Picture Show that those seedlings have really germinated from the very Special shaped grains coming out of the fruit of the one Asminia pollinated Cherimoya flower which I posted  here some months ago ,
(https://i.postimg.cc/zbzPpx9H/DSC07002.jpg) (https://postimg.cc/zbzPpx9H)

(https://i.postimg.cc/QVVftKsD/DSC07003.jpg) (https://postimg.cc/QVVftKsD)

(https://i.postimg.cc/XZV80pxT/DSC07004.jpg) (https://postimg.cc/XZV80pxT)

(https://i.postimg.cc/WtD7jR6b/DSC07005.jpg) (https://postimg.cc/WtD7jR6b)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on July 13, 2019, 10:18:50 AM
Now the time has come to start second trial of hybridization using Cherimoya as mother and Asiminia as father - because in the new season the first Cherimoya flower began to open. I took pollen from Asiminia "Prima 1216"- see photos enclosed. For the next fowers which will follow I will also use pollen of several other Asiminia varieties. Please see photos enclosed of pollinating.
(https://i.postimg.cc/mcFznr46/DSC07125.jpg) (https://postimg.cc/mcFznr46)

(https://i.postimg.cc/rdWsJYGB/DSC07127.jpg) (https://postimg.cc/rdWsJYGB)

(https://i.postimg.cc/mPg7mRh0/DSC07130.jpg) (https://postimg.cc/mPg7mRh0)

(https://i.postimg.cc/sQ7WMg0Z/DSC07133.jpg) (https://postimg.cc/sQ7WMg0Z)

(https://i.postimg.cc/xkCDjk8t/DSC07135.jpg) (https://postimg.cc/xkCDjk8t)

(https://i.postimg.cc/QHTcPSqq/DSC07138.jpg) (https://postimg.cc/QHTcPSqq)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on July 13, 2019, 11:04:58 AM
Very cool!
I’d never seen a cherimoya flower before.

When was the Asimina pollen collected?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on July 13, 2019, 12:05:31 PM
@ Triloba Tracker: Thanks for your reply. To your question: I collected Asiminia pollen from several varieties of Paw Paw end of April 2019 and stored it frozen at -25 °C ( -13 °F) until today when I used it the first time. I have taken several other samples of pollen which I still will keep frozen for pollinating next flowers...As it looks like many Cherimoya flowers willl flower in the next weeks - an I will have this time enough Asimina pollen  - frozen in several little cartridges to be able to thaw and use them individually for the several planned pollinations - means to have for each pollination a new pollen batch available.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on July 13, 2019, 01:00:28 PM
Sounds like a great plan
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on July 19, 2019, 04:00:42 PM
Today I will give some updates:

1. One of the seedlings of the crossing which I did last year Chemimoya (Mother) x Asiminia (Father) by using dried pollen shows crippled growth. Possibly a real hybrid? With the different number of chromosomes of the two parents, it is possible that no normal behaviour can be expected in such a difficult cross... Who knows? We will see...

(https://i.postimg.cc/hfYP9D2V/DSC07200.jpg) (https://postimg.cc/hfYP9D2V)

(https://i.postimg.cc/dDHqYQPg/DSC07201.jpg) (https://postimg.cc/dDHqYQPg)


2. the recently pollinated flower of Cherimoya is still hanging and it has not (?) dried up. It seems as if the fruit set is still struggling with whether it was really pollinated or not. An unpollinated flower of Cherimoya would have dried out after this time. A properly pollinated flower would have a thicker stalk...so the result is somehow in between. Let's see what else is going on! In contrast to last year I had not pollinated with Chermioya pollen at a later time.

(https://i.postimg.cc/sM0f4VKp/DSC07196.jpg) (https://postimg.cc/sM0f4VKp)


3. Cherimoya's second flower this season (and the last one for a long time to come) will probably wait for pollination tomorrow. I will pollinate this time with pollen from Sunflower.

(https://i.postimg.cc/MX8BQDnz/DSC07202.jpg) (https://postimg.cc/MX8BQDnz)

4. One of the in last spring pollinated flowers Asiminia (Mother)  x Cherimoya iincludes is still alive - we had freezes after flowering time, therefore many Young fruits Drops down, also normally pollinated fruits. So I hope that ithis fruit will grow further and get ripe- maybe it includes also norma asininia seeds, because I was not able to exclude to 100% pollination by insects.


(https://i.postimg.cc/ykyydGnq/DSC07181.jpg) (https://postimg.cc/ykyydGnq)

Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on July 27, 2019, 04:53:18 PM
Who from you have sometimes seen any seedlings from Cherimoya? Maybe anyone of you has actuallay some seedlings of Cherimoya in his collection?

The reason for my question - the seedlings of my potential crossings show only few hairs on the bottom side of the leafes - in opposite to this the mother plant shows a lot of hairs on the lower side of ist leafes.

Do you know if Cherimoya seedlings firs have less hairs on their leafes and develop more and more hairs as older they get?
(This pould help to evualate the possibility of getting really crossed Cherimoya with Asiminia.
Just for information: Asiminia does show nearly no hairs on the lower side of ist leafes - therefore my question)

Please find enclosed some prictures with show the bottom side of some leafes:


- Bottom side of the leafes of young seedlings - potentially Chermimoya x Asiminia seedlings - show only few hairs
(https://i.postimg.cc/8JYHYQtj/DSC07395.jpg) (https://postimg.cc/8JYHYQtj)

- Bottom side of the leafes of the mother plant - Show a lot of hairs
(https://i.postimg.cc/JDs3ZYMm/DSC07397.jpg) (https://postimg.cc/JDs3ZYMm)

- Bottom side of the leafes of Asminia triloba - Show nearly no hairs
(https://i.postimg.cc/HcbxqbtX/DSC074312.jpg) (https://postimg.cc/HcbxqbtX)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: SeaWalnut on July 28, 2019, 08:45:19 PM
This is my cherimoya seedling.I put somewhone to take the picture and its not too clear to heellp you.
(https://i.postimg.cc/cCmWjGWN/IMG-20190728-WA0001.jpg)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: mikkel on July 31, 2019, 05:44:25 PM
@usirius
Here is another picture of a cherimoya seedling
https://ibb.co/hfNVTFM (https://ibb.co/hfNVTFM)

this is the thread
http://citrusgrowersv2.proboards.com/thread/131/cherimoya-seedlings (http://citrusgrowersv2.proboards.com/thread/131/cherimoya-seedlings)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on July 31, 2019, 06:25:35 PM
@SeaWalnut - Thank you for the picture. Seem to Show similar or some more hairs on the down side of the leaf. I have a question: Is the seedling still so somall or did it grow bigger and Show more hairs on the bottom of the leafes?

@Mikkel - Thank you for the link. Your seedling show as many hair as the mother plant of my seedlings do, but it also seem to be a Little bit elder than my seedlings are. I have a question: Did this seedling show significant less hairs on the bottom when it has been younger on ist first leafes?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: mikkel on July 31, 2019, 06:30:13 PM
@usirius sorry but it is not my picture. I just found that thread on the other forum and asked for a picture. I can ask there if you like or you get in touch via the othe forum.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 13, 2019, 05:25:02 PM
Now I had the luck to get some seedlings of Asimina triloba for better comparison.

So see here the comparison of Asimina triloba seedlings and the possible Cherimoya-Asimina-Hybrid seeldings:

(https://i.postimg.cc/MnJ6QRks/DSC07770.jpg) (https://postimghttp://tropicalfruitforum.com/index.php?action=post;topic=15345.50;last_msg=361015#.cc/MnJ6QRks)

(https://i.postimg.cc/5jHbKpb7/DSC07769.jpg) (https://postimg.cc/5jHbKpb7)


So they are of course different as expected..

When comparing the foliage of the possible hybrid seedlings with the foliage of their mother plant Cherimoay - the are a little bit different- see the hairs, the colour of the sprouts....

(https://i.postimg.cc/Wq7BqD0y/DSC07765.jpg) (https://postimg.cc/Wq7BqD0y)

(https://i.postimg.cc/zLt3KBFV/DSC07763.jpg) (https://postimg.cc/zLt3KBFV)


But when I compare the seedlings of Asimina with ist mother plants there are also some differences....

(https://i.postimg.cc/sGyXRhVH/DSC07774.jpg) (https://postimg.cc/sGyXRhVH)

(https://i.postimg.cc/Wt3p0Tdk/DSC07772.jpg) (https://postimg.cc/Wt3p0Tdk)


What is your opinion - are the possible hybrd seelings really hybrids?

Nevertheless I started new trials of hybridisation of Cherimoya and Asininia as already announced in spring by using Asimina asmother and now by using agan Cherimoya as mother, here are some results:

(https://i.postimg.cc/0ML88J91/DSC07801.jpg) (https://postimg.cc/0ML88J91)

(https://i.postimg.cc/y3c7WYNg/DSC07802.jpg) (https://postimg.cc/y3c7WYNg)

(https://i.postimg.cc/HjwxpB8S/DSC07806.jpg) (https://postimg.cc/HjwxpB8S)


So: It remains exciting.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on August 13, 2019, 09:14:19 PM
Way to experiment!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on August 13, 2019, 09:48:47 PM
Way to experiment!

I was going to say the same thing :)
I think generally with seedlings it’s hard to tell a lot. Especially when comparing to a mature plant.
I think all we can do is wait and see. Those fruits look good!
This is exciting indeed.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: NickTheNZgrower on August 13, 2019, 11:41:57 PM
To my eye, your seedlings look different to ordinary cherimoya seedlings. To me, there is real hope that this could be a real hybrid. I can't wait to see more mature plants and eventually what the flowers and fruit looks like.

Please keep us updated :) You should eventually be able to graft a piece of the "Hybrid" seedling to a mature fruiting cherimoya and get flowers faster.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 14, 2019, 05:31:16 PM
@All: Thanks for your comments. Yes, I also think that the comparison of young plants with adult plants is limping.  Unfortunately, I don't have any Cherimoya seedlings to be able to compare the hybrid seedlings with them. Time will tell. Nonetheless - regardless of whether it worked the first time or not, I have further trials running and there will be results here as well. Maybe I will attract pure Cherimoya seedlings to have a comparison, or one of you happens to have Cherimoya seedlings of comparable age. The tip to add rice to an adult plant for an earlier flower is good. If I know of citrus plants, which I have worked on intensively for many years, this trick can also be used successfully there.
I will keep you informed - of course.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: SeaWalnut on August 15, 2019, 04:15:13 AM
My cherimoya seedling to use it for comparison.
(https://i.postimg.cc/k4qpcpYS/IMG-20190815-WA0032.jpg)

(https://i.postimg.cc/4NQbv3kW/IMG-20190815-WA0016.jpg)

(https://i.postimg.cc/qvcY3rjr/IMG-20190815-WA0031.jpg)

(https://i.postimg.cc/KvjBTDf8/IMG-20190815-WA0004.jpg)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 15, 2019, 06:07:36 PM
Thanks @SeaWalnt for sharing so much pictures of your Cherimoya seedlings. For me your seedlings show a little bit more hairs han my seedlings of the potential hybrid. But I can well imagine that there are scatters among cherimoya plants as far as hair formation is concerned. There are also differences in the shape of the leaves: I myself have two different types, one with a rounded leaf end and one with a pointed leaf end. Tomorrow in daylight I will compare your photo with my local plants and post one or two macro shots of the leaf hair and the leaf tip.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 16, 2019, 02:48:12 AM
Today in the morning I took some additional pictures from the potential crossings Cherimoya x Asimina
With a better resolution of my camera I was able to see that those seedlings show more hairs than I have seen with my eyes an felt with my hands.


(https://i.postimg.cc/r0qGpgGd/DSC07811.jpg) (https://postimg.cc/r0qGpgGd)

(https://i.postimg.cc/2V1Q31Wx/DSC07812.jpg) (https://postimg.cc/2V1Q31Wx)

(https://i.postimg.cc/vg89yTMf/DSC07813.jpg) (https://postimg.cc/vg89yTMf)

(https://i.postimg.cc/7CwJ1h5d/DSC07815.jpg) (https://postimg.cc/7CwJ1h5d)

(https://i.postimg.cc/WqFdpJyF/DSC07816.jpg) (https://postimg.cc/WqFdpJyF)

So in comparison to @SeaWalnuts's Cherimoya seelings they seem to be very similar as to the hairiness.

So at this point, my opinion is that hybridization probably did not work. So I am hoping that my  further attempts will show more further trials will show more significant hybridization successes.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: SeaWalnut on August 16, 2019, 03:16:08 AM
Dont hurry to assume that it didnt work.You are most likely right ,but its still too early to tell.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on August 16, 2019, 07:38:20 AM
I would separate them into individual pots, to observe further.  At the very least, they will be good for root-stocks.   If you put grafts onto them when they are three or four feet tall and with more than one branch, you can leave one branch without a graft, to evaluate its fruit.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on August 16, 2019, 08:52:34 PM
I agree - don’t give up! A healthy pessimism is o k but it could still be a cross.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 18, 2019, 09:04:29 AM
@All:
Thanks for sharing your opinions and thank you for your realistic assessments, advice and encouraging words. So I will observe the plants for a while and maybe this year I will also create a pure Cherimoya pollinated Cherimoyaflower to get real Cherimoya seeldings from my mother plant as base for comparison - this will happen earliest next year of course, so long I will keep on watching the current seedlings and creating new pollinations on the few remaining Cherimoya flowers of my Cherimoya plant. Sorryly most of the Asimina-pollinated Cherimoya flowers dried within two or three weeks. With Asimina pollinated Cherimoya flowers stay more longer alive than time unpollinated Cherimoya flowers is until they dry out - but most of Asimina-pollinated Cherimoya flowers die within two to three weeks. But a few are stiill alive and I hope that they will remain alive and no insect has helped me by doing pollination...
I will keep you informed.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Radoslav on August 20, 2019, 10:19:59 AM
I am not a specialist, but if the situation is similar to crossing diploids with tetraploids in citrus breeding, then it will be impossible to save embryo without separation and rising in vitro.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 21, 2019, 10:20:58 AM
@Radislav: Thanks for your post. I think, and certainly most of the members of the forum who deal with hybridization, that it's as you write. By the way, we discussed this topic here in this section some time ago. Nevertheless, it cannot be excluded that pollination is successful even with different chromosome numbers of cross partners, because it can also be assumed that degenerated or modified cells or Cell information can be contained, further can by tricks such as the use of gibberlic acid (which I have not yet tried, I will still try next year), further also post-pollination with own pollen, inverse hybridization, hybridization of one among themselves incompatible individuals (I have such an Asimina) with Annona, and certainly still further possibilities then nevertheless a hybrid can develop, to what extent this forms a complete germinable seed, and to what extent this forms again a viable plant, is the question. Perhaps one would have to try to hybridize plants of the Annona family with more closely related Annonas (Atemoya) via a detour of hybrids. I think that, despite scientific evidence and experience, surprises might be possible.We will see.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on August 21, 2019, 08:48:38 PM
Another technique, not mentioned above, is pre-germinating pollen before applying it to the pistil.  But I have no knowledge of how to do that.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 22, 2019, 04:09:16 PM
 Thank you for sharing the hint to another interesting sounding  method - I will do a research concerning  this. In case if success I let you know if course.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 24, 2019, 02:58:08 AM
Concerning pretreatment of pollen I found interesting literature. Handicap is in vitro culture but with this method one would have much more possibilities as can be read here - just two articles as for example:

https://www.intechopen.com/books/pollination-in-plants/pollen-germination-in-vitro (https://www.intechopen.com/books/pollination-in-plants/pollen-germination-in-vitro)

Pollen Germination in vitro

By Jayaprakash P
Submitted: November 20th 2017Reviewed: February 13th 2018Published: June 6th 2018
DOI: 10.5772/intechopen.75360

Abstract

Pollen germination in vitro is a reliable method to test the pollen viability. It also addresses many basic questions in sexual reproduction and particularly useful in wide hybridization. Many pollen germination medium ranging from simple sugars to complex one having vitamins, growth regulators, etc. in addition to various minerals have been standardized to germinate pollen artificially. The different media, successful pollen germination methods, procedures from pollen germination studies with wheat, rye, brinjal, pigeonpea and its wild relatives are discussed.



http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100009 (http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100009)

Pollen treatment in high osmotic potential: a simple tool for in vitro preservation and manipulation of viability in gametophytic populations

By: Leandro Lopes Loguercio 
Departamento de Ciências Biológicas - DCB, Universidade Estadual de Santa Cruz, Rod. Ilhéus-Itabuna, Km 16, Ilhéus, BA, 45650-000, Brasil; E-mail: leandro@uesc.br

Brazilian Journal of Plant Physiology
On-line version ISSN 1677-9452
Braz. J. Plant Physiol. vol.14 no.1 Londrina Jan./April 2002
http://dx.doi.org/10.1590/S1677-04202002000100009 (http://dx.doi.org/10.1590/S1677-04202002000100009) 

Abstract

A method for in vitro preservation and manipulation of pollen viability based on simple changes in osmotic potential (sucrose concentrations) in culture media was developed using tobacco pollen as the experimental model. High osmotic potentials were capable of reversibly inhibiting pollen germination, preserving its viability at room temperature for long periods, as assessed by subsequent incubation in germination medium. When pollen was pre-germinated for different periods and subsequently incubated in 80 % sucrose medium (inhibiting medium) there was a progressive decrease in its viability, which was a trend best described by a quadratic regression line. Nevertheless, very small variations in pollen-tube lengths and viable pollen grains more resistant to the pre-germination step were detected by this procedure. Consequences and potential applications of these findings were discussed for use in analyses of variability, selection in gametophytic populations and pollen storage.

Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 30, 2019, 02:37:46 PM
Interim report on my pollination attempts of Cherimoya flowers with Asimina pollen this year: After varying many different parameters, I came to the conclusion that it is possible to obtain fruit by pollinating cherimoya flowers with Asimina pollen. To what extent these fruits contain germinable seeds, and if the seedlings are actual hybrids or nucellar species, remains to be seen. Here are some photos:

1) These following two pictures show fruits, which were probably pollinated by others. Here I did not protect the flowers from pollination by insects. So insects may have pollinated those flowers succesfull with Cherimoya pollen:


(https://i.postimg.cc/mPLJ7RP9/DSC08147.jpg) (https://postimg.cc/mPLJ7RP9)

(https://i.postimg.cc/ts8cw6r3/DSC08150.jpg) (https://postimg.cc/ts8cw6r3)

2) These follwing three pictures show dried fruit preparations in which pollination definitely did not work.

(https://i.postimg.cc/bdvR0Jgp/DSC08148.jpg) (https://postimg.cc/bdvR0Jgp)

(https://i.postimg.cc/hXRxYPLJ/DSC08149.jpg) (https://postimg.cc/hXRxYPLJ)

(https://i.postimg.cc/7JTGBpbM/DSC08152.jpg) (https://postimg.cc/7JTGBpbM)

3) These following two pictures Show two fruit sets where pollination worked and which are now obviously developing. Those flowers have definitvely got only Asimina pollen and no Cherimoya pollen!

(https://i.postimg.cc/vgyGRkPt/DSC08151.jpg) (https://postimg.cc/vgyGRkPt)

(https://i.postimg.cc/TpBMMB15/DSC08154.jpg) (https://postimg.cc/TpBMMB15)

Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 07, 2019, 04:25:37 AM
After about 30 different pollination tests I did this season on a grafted Cherimoya tree with several variation of various parameters, I have come to the conclusion that pollination of Cherimoya flowers with Asimina pollen is quite possible under certain conditions. Now I start a second series of tests on a Cherimoya seedling that is flowering for the first time.  At the moment it has one flower open, there is no other Cherimoya flowering in the area - at least in a radius of 10 kilometres. So this time pollination by insects with Cherimoya pollen is definitely impossible.  Now I have carried out the pollination exactly with the same procedure with same parameters and criteria, which according to my knowledge lead to success - i.e. to the formation of a fruit. I will report to you whether the fruit batch is developing.

(https://i.postimg.cc/RWT1fmsN/DSC08360.jpg) (https://postimg.cc/RWT1fmsN)

(https://i.postimg.cc/JGNjVmWP/DSC08355.jpg) (https://postimg.cc/JGNjVmWP)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on September 07, 2019, 08:45:28 AM
One can close a flower with a small rubber grafting strip, or a rubber band, before and after hand-pollination, to exclude pollinators.

This can also retain higher humidity inside the flower's chamber, thus extending the viability of the pollen that you place there.

On the down-side, it is theoretically possible that this higher humidity and darkness would keep the stigmas receptive, until the flower's own pollen is released, so you might want to remove the band a few hours before male stage.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 08, 2019, 04:09:57 PM
Hi Guanabanus, sounds interesting, and Logical! Perhaps in the course of evolution Chermioya has developed from a formerly open flower to a flower closed during pollination in order to protect the pistils from dehydration and to keep the pollen as viable as possible and to optimise the pollination process. The additional closing by means of rubber band or adhesive tape could actually successfully prevent foreign pollination by insects, but depending on the humidity in the air and the temperature, it would also be possible for the pollen to form a cloud, possibly of your own pollen, if the flower changes into the male phase and you open it again too late. It would be worth a try in the next season in any case - I would consider this approach and try if this year's successful looking hybridized flowers would not have produced real hybrids at a later point in time.What I have also noticed, by the way, and what speaks a little to the assumption about you regarding the humidity in the flower, is that the pollination success also seems to depend on the weather conditions, i.e. whether it rains, whether the sun shines, whether it is cooler, whether it is hot, etc. This actually seems to have an influence on the success of pollination.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: CherimoyaDude on August 29, 2020, 12:47:06 AM
Diploid Asimina/Anona hybrids that Usirius is trying to produce will most probably be non fertile since two parents have different chromosome numbers.
But crossing the combination of two tetraploids will give a tetraploid hybrid with balanced chromosome number. This could be done either by a generation of tetraploid Asimina and Anona by colchicine  or oryzalin treatment and than crossing such plants, or by pollination of hybrid  atemoyas with an excess of Asimina pollen.

Triloba Tracker,
I do not think that triploid asimina will be very fertile like triploid citrus varieties.

How do tetraploid hybrids work if the have a different number of chromosome?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on August 29, 2020, 07:18:44 PM
It is very interesting that hybridization in nature also works differently, as known from Mendel's law. Partly there are demarcations and formation of new species after hybridizations. It is amazing that many of our cultivars were made possible by hybridization of species with different sets of chromosomes, and this was possible 1000's of years ago without genetic engineering! How does that work? Quite simply, in meiotic mating, plants have the possibility to double the DNA without cell division by endomitosis, making the cell tetraploid. If the number of chromosomes doubles to (allo)tetraploidy by mitotic nondisjunction (endomitosis), the hybrids can make normal reduction division, because for each chromosome there is a homologous partner with which it can mate during meiosis.

(source: https://www.kunz.hhu.de/fileadmin/redaktion/Fakultaeten/Mathematisch-Naturwissenschaftliche_Fakultaet/Biologie/Institute/weitere_und_ehemalige_Dozenten/Prof._Dr._Kunz/07_Haldane_hybridogene_Artbildung.ppt (https://www.kunz.hhu.de/fileadmin/redaktion/Fakultaeten/Mathematisch-Naturwissenschaftliche_Fakultaet/Biologie/Institute/weitere_und_ehemalige_Dozenten/Prof._Dr._Kunz/07_Haldane_hybridogene_Artbildung.ppt))
 
Of course this effect can be provoked by various methods, as described in previous posts. But my hope is that it works without supporting measures, and I have received fruit attachments that definitely did not come from pollination with its own pollen. Now it is time to attract seedlings from the seed and to evaluate them.



Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 02, 2020, 02:41:49 PM
Concerning my hybridization trial I am now sharing some actual pictures:

- Original mother plant Annona cherimola without pronounced leaf tip


(https://i.postimg.cc/5YN9ymQ2/Annona-cherimola-1.jpg) (https://postimg.cc/5YN9ymQ2)

(https://i.postimg.cc/jLCWZR5S/Annona-cherimola-2.jpg) (https://postimg.cc/jLCWZR5S)



- Original father plant Asimina triloba with pronounced leaf tip


(https://i.postimg.cc/Fkk4kCrN/Asimina-triloba-1.jpg) (https://postimg.cc/Fkk4kCrN)

(https://i.postimg.cc/jwmVT6z9/Asimina-triloba-2.jpg) (https://postimg.cc/jwmVT6z9)


- hybrid (?) seedlings with pronounced leaf tip

(https://i.postimg.cc/4n9qt9vf/Seedling-1.jpg) (https://postimg.cc/4n9qt9vf)

It is not yet a proof, but it is an interesting feature, and of course it is up to the individual to form an opinion about whether the hybridization has worked. I will raise a part of the seedlings until flowering, and I have also produced other hybrid fruits on both parents, which are now ripening and whose seeds will be sown next year.  I am confident that I have achieved a breakthrough here.


Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on September 02, 2020, 05:06:55 PM
Thank you for the update.  The plant shown is in beautiful health.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 03, 2020, 02:45:49 PM
Thank you Guanabanus for your feedback.

Now as you mention this  I have realized that the seedlings which have sprout in June/July are growing extremely vigorously, even though they are crammed together in a relatively small flower pot with not very valuable soil, and that they are twelve in one, maybe the vigor is another sign that the seedlings are hybrids? Because hybrids often grow stronger than their parents. And a double set of chromosomes would also lead to stronger growth, which could also explain the extremely large leaves for these young plants, which are also full sunny - just like the cherimoya mother plant, which has much smaller leaves :-)
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on September 04, 2020, 04:43:39 AM
Maybe.

But it is also normal for juveniles to have much larger leaves than the adult plants do.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 04, 2020, 04:48:05 AM
Yes, that may well be, although I have had cherimoya seedlings with much smaller leaves. You have to know that we had a lot of heat and sun this year, and the seedlings were always in full sun. Due to the circumstances, they should have made rather small leaves, but they didn't! I will of course continue to observe what happens.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 04, 2020, 10:02:31 AM
Call me lazy for not going back and reading all the prior posts...

Usirus, if the crossing was done in a controlled way with proper methods to exclude contamination, there would be no doubt about whether the seedling is a hybrid, no?

If so, what are your impediments to making sure there is no contamination? I've never tried it and I agree that there would maybe always be a sliver of doubt in your mind, BUT it seems like it shouldn't be too hard .... (experts, feel free to destroy my naivete :))
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on September 04, 2020, 01:23:07 PM
There is evidence, that certain conditions can occur, in which a flower literally self-pollinates;  so, careful prevention of contamination from the outside, though the main concern, is not a guarantee.

There have been multiple instances of plant breeders of good repute actually growing out plants that were eventually identified as not being hybrids at all.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on September 04, 2020, 01:37:31 PM
Makes sense, Har - good to know!

Caution is always a good thing when dealing with plants, it seems.
Thanks!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 04, 2020, 05:05:33 PM
@TrilobaTracker and @Guanabanus- Thank you for your contributions and thoughts. Well, I have excluded 99,9% of external influences, because on the one hand the flowers have bloomed single and on the other hand I have protected them against possible cross-pollination by insects with a microporous bag. If self-pollination has occurred, it is something I had no influence on, and I do not want to exclude it, and that is - if the seedlings are not hybrids - with 99,9% probability. But what makes me positive is that by varying many parameters I was able to optimize - beginning by the selection of the optimal pollen donor for pollination up up to more and more refinement of the process steps and boundary conditions to achieve the greatest possible probable pollination success, and this reproducible. This means, that there are many important things you have to pay no attention to, and here the right time of pollination is the least problem. Then I also noticed that there is a clear difference between pollinating Cherimoya flowers with cherimoya pollen and pollinating Cherimoya flowers with Pawpaw pollen. If Cherimoya flowers are pollinated with Cherimoxya pollen, it takes a few days and you can see that the pollination is successful and the ovary grows. If Cherimoya flowers are pollinated with Pawpaw pollen, it takes weeks and you get the impression that the plant is thinking about whether this was a pollination at all. And during this time most pollinated ovaries fall off. And a few of them, after several weeks, begin to decide to stay on and grow very slowly. This could be an indication of meiotic chromosome duplication without cell division. I can say more if the seedlings are in an older stage. At the same time I am also producing the inverse hybrid on Pawpaw as mother plant and I have also some more this year's fruit sets with pollination by Pawpaw pollen on the Cherimoya mother plant, which are a bit bigger than pinhead size.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: micawi on September 04, 2020, 05:28:15 PM
keep us posted
Title: Re: Cherimoya/Pawpaw hybrid
Post by: CherimoyaDude on September 04, 2020, 08:04:20 PM
Is there a way to genetically test the leaf? Maybe some university nearby that has something that could count the chromosomes?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Gogu on September 04, 2020, 10:09:56 PM
This is super exciting stuff. Thank you for doing this experiment.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on September 04, 2020, 10:52:08 PM
That delay in fruit-set development is very interesting!

I don't recall having observed that.

I did sometimes observe the opposite, where foreign pollinations would be rejected so fast that there seemed to be an allergic reaction.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 05, 2020, 02:17:07 AM
keep us posted
Yes I will share any news here. Soon I will harvest the first Pawpaw fruit which flower has polinated with Cherimoya pollen. From this fruit and fromthe seeds I will share pictures.

Is there a way to genetically test the leaf? Maybe some university nearby that has something that could count the chromosomes?
Certainly there are institutes and universities here that could carry out a genetic analysis. Years ago, I wanted to have one done on a very interesting Vitis hybrid, which I created by open pollination, and I have contacted several institutions. Most of them refused, because they are busy with their own work, and the few who would have done it, demanded unreasonably much money. So I prefer to wait until I can see from other characteristics whether I have achieved hybrids or not. And if it worked, the chromosome set has to be doubled, because of the different chromosome sets of Cherimoya and Pawpaw.

This is super exciting stuff. Thank you for doing this experiment.
Thank you - you are welcome! I have to admit, it is also fun and all objections, comments and suggestions are inspiring and absolutely valuable for the evaluation and further development of this experiment!

That delay in fruit-set development is very interesting!

I don't recall having observed that.

I did sometimes observe the opposite, where foreign pollinations would be rejected so fast that there seemed to be an allergic reaction.
Interesting is also your observation and I think this does not contradict my observation, because the majority of Cherimoya flowers pollinated with Pawpaw pollen reacts in principle as u wrote, a very short time passes, mostly even shorter than if the flowers had not been pollinated, and the flower dries up and dies, The death of the flower is different and may give an indication whether perhaps genetic processes have already started or not. Some flowers dry out very quickly and evenly, i.e. petals and base of fruit, and some flowers first let the three petals dry out - like a dry mummy, which often remains loose at the base of fruit - and then dry out later with a little delay.


Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on September 05, 2020, 01:17:08 PM
Chromosome doubling can happen, but usually doesn't.  Colchicine can be used, theoretically at least, to cause chromosome doubling on a new branch of the hybrid plant.  I never tried this, I have not heard of anyone's having had any success doing that with Annona species or hybrids.

Another event that happens is that a new hybrid, made with parents having different numbers of chromosomes, can be like a mule, having an uneven number of chromosomes.  These usually cannot make viable offspring, so no good seeds from these hybrids' fruit.  Or, they can't fruit at all.  I made "mules" like that when I pollinated Guanabanus muricatus (Annona muricata) with pollen from Guanabanus coriaceus (Annona coriacea)--- two plants, never any fruits, no matter what I pollinated their many flowers with.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 05, 2020, 04:11:18 PM
@ Guanabanus
Very constructive and interesting - your report on the hybrid you made - thank you for this Information!.


Yes absolutely, a polyploid hybrid does not have to be fertile.

Also there are examples which show that polyploidy can help to get fertile plant  hybrids. The cereale hybrid Triticiale - a cross between wheat (Triticum aestivum L.) as the female and rye (Secale cereale L.) as the male partner (×Triticosecale or Triticosecale Wittmack) ) the chromosome sets were doubled by using colchicine in the seedlings to obtain fertile offspring. In other words, the doubling of the chromosome sets could only lead to reproductive ability. Triticiale offsprings are usually selsbstungen from Trticicale x Triticiale h itself would actually have the possibility to work with colhizin, but I have not yet worked with it. I would have to read in and study the method, then I could also use it on the Annonaceae.

At this point I like to remember to one of my last posts - to the presentation which takes a summary of

Haldan's rule and the hybridogenic speciation and postzygotic incompatibility. Haldane (1892-1964) was a British Indian geneticist.

https://www.kunz.hhu.de/fileadmin/redaktion/Fakultaeten/Mathematisch-Naturwissenschaftliche_Fakultaet/Biologie/Institute/weitere_und_ehemalige_Dozenten/Prof._Dr._Kunz/07_Haldane_hybridogene_Artbildung.ppt (https://www.kunz.hhu.de/fileadmin/redaktion/Fakultaeten/Mathematisch-Naturwissenschaftliche_Fakultaet/Biologie/Institute/weitere_und_ehemalige_Dozenten/Prof._Dr._Kunz/07_Haldane_hybridogene_Artbildung.ppt) (Sorry that it is written in German language. But the pictures will help to explain.)

So in genetics everything is possible. From no result to infertility to the emergence of a separate species with differentiation by developing an incompatibility to backcrossing with the parents. In the plant kingdom the development of incompatible hybrids

At this point I would also like to refer to another interesting report and quote from it: I think some of you, you maybe anyway, I will already know, A. muricata is also mentioned, sorry not A. coriacea )

Polyploidy in Fruit Tree Crops of the Genus Annona (Annonaceae)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/ (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/)
https://www.researchgate.net/publication/331019625_Polyploidy_in_Fruit_Tree_Crops_of_the_Genus_Annona_Annonaceae/fulltext/5c6181d692851c48a9ca964d/Polyploidy-in-Fruit-Tree-Crops-of-the-Genus-Annona-Annonaceae.pdf (https://www.researchgate.net/publication/331019625_Polyploidy_in_Fruit_Tree_Crops_of_the_Genus_Annona_Annonaceae/fulltext/5c6181d692851c48a9ca964d/Polyploidy-in-Fruit-Tree-Crops-of-the-Genus-Annona-Annonaceae.pdf)
"Genome duplication or polyploidy is one of the main factors of speciation in plants. It is especially frequent in hybrids and very valuable in many crops. (...) Surprisingly, while the hybrid atemoya has been reported as diploid, flow cytometry analysis of a progeny obtained from an interspecific cross between A. cherimola and A. squamosa showed an unusual ploidy variability that was also confirmed karyotype analysis. hile the progeny from intraspecific crosses of A. cherimola showed polyploid genotypes that ranged from 2.5 to 33%, the hybrid atemoyas from the interspecific cross showed 35% of triploids from a total of 186 genotypes analyzed. With the aim of understanding the possible implications of the production of non-reduced gametes, pollen performance, pollen size and frequency distribution of pollen grains was quantified in the progeny of this cross and the parents. A large polymorphism in pollen grain size was found within the interspecific progeny with higher production of unreduced pollen in triploids (38%) than in diploids (29%). Moreover, using PCR amplification of selected microsatellite loci, while 13.7% of the pollen grains from the diploids showed two alleles, 41.28% of the grains from the triploids amplified two alleles and 5.63% showed up to three alleles. This suggests that the larger pollen grains could correspond to diploid and, in a lower frequency, to triploid pollen. Pollen performance was also affected with lower pollen germination in the hybrid triploids than in both diploid parents. The results confirm a higher percentage of polyploids in the interspecific cross, affecting pollen grain size and pollen performance. The occurrence of unreduced gametes in A. cherimola, A. squamosa and their interspecific progeny that may result in abnormalities of ploidy such as the triploids and tetraploids observed in this study, opens an interesting opportunity to study polyploidy in Annonaceae.
(...)
Polyploidy is believed to be a major mechanism of adaptation and speciation, recognized as a major force in evolution (Van de Peer et al., 2017) and very valuable for crop improvement (Udall and Wendel, 2006; Mason, 2016). Polyploidy is more common in plants than in animals. It is estimated that between 30 and 70% of extant flowering plant species are polyploids (...)"

More I will not paste here. The best is to study the complete report by yourself!

Bytheway...to my new hybridizations of this year there is again a small setback. One of the ovaries, which took weeks to show that pollination was successful, has now decided to dry out after some growth. Another one is still in good shape, I hope it stays that way. Last year, such an ovary grew into a strongly deformed fruit, which is another sign of an unusual way of embryo formation. Unfortunately this fruit dried up in centimeter size and still hangs on the tree like a mummy. I have pictures, but I do not want to overload this post!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 05, 2020, 04:13:33 PM
@ Guanabanus
Very constructive and interesting - your report on the hybrid you made - thank you for this Information.


Yes absolutely, a polyploid hybrid does not have to be fertile.

Also there are examples which show that polyploidy can help to get fertile plant  hybrids. The cereale hybrid Triticiale - a cross between wheat (Triticum aestivum L.) as the female and rye (Secale cereale L.) as the male partner (×Triticosecale or Triticosecale Wittmack) ) the chromosome sets were doubled by using colchicine in the seedlings to obtain fertile offspring. In other words, the doubling of the chromosome sets could only lead to reproductive ability. Triticiale offsprings are usually selsbstungen from Trticicale x Triticiale h itself would actually have the possibility to work with colhizin, but I have not yet worked with it. I would have to read in and study the method, then I could also use it on the Annonaceae.

At this point I like to remember to one of my last posts - to the presentation which takes a summary of

Haldan's rule and the hybridogenic speciation and postzygotic incompatibility. Haldane (1892-1964) was a British Indian geneticist.

https://www.kunz.hhu.de/fileadmin/redaktion/Fakultaeten/Mathematisch-Naturwissenschaftliche_Fakultaet/Biologie/Institute/weitere_und_ehemalige_Dozenten/Prof._Dr._Kunz/07_Haldane_hybridogene_Artbildung.ppt (https://www.kunz.hhu.de/fileadmin/redaktion/Fakultaeten/Mathematisch-Naturwissenschaftliche_Fakultaet/Biologie/Institute/weitere_und_ehemalige_Dozenten/Prof._Dr._Kunz/07_Haldane_hybridogene_Artbildung.ppt) (Sorry that it is written in German language. But the pictures will help to explain.)

So in genetics everything is possible. From no result to infertility to the emergence of a separate species with differentiation by developing an incompatibility to backcrossing with the parents. In the plant kingdom the development of incompatible hybrids

At this point I would also like to refer to another interesting report and quote from it: I think some of you, you maybe anyway, I will already know, A. muricata is also mentioned, sorry not A. coriacea )

Polyploidy in Fruit Tree Crops of the Genus Annona (Annonaceae)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/ (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6378316/)
https://www.researchgate.net/publication/331019625_Polyploidy_in_Fruit_Tree_Crops_of_the_Genus_Annona_Annonaceae/fulltext/5c6181d692851c48a9ca964d/Polyploidy-in-Fruit-Tree-Crops-of-the-Genus-Annona-Annonaceae.pdf (https://www.researchgate.net/publication/331019625_Polyploidy_in_Fruit_Tree_Crops_of_the_Genus_Annona_Annonaceae/fulltext/5c6181d692851c48a9ca964d/Polyploidy-in-Fruit-Tree-Crops-of-the-Genus-Annona-Annonaceae.pdf)
"Genome duplication or polyploidy is one of the main factors of speciation in plants. It is especially frequent in hybrids and very valuable in many crops. (...) Surprisingly, while the hybrid atemoya has been reported as diploid, flow cytometry analysis of a progeny obtained from an interspecific cross between A. cherimola and A. squamosa showed an unusual ploidy variability that was also confirmed karyotype analysis. hile the progeny from intraspecific crosses of A. cherimola showed polyploid genotypes that ranged from 2.5 to 33%, the hybrid atemoyas from the interspecific cross showed 35% of triploids from a total of 186 genotypes analyzed. With the aim of understanding the possible implications of the production of non-reduced gametes, pollen performance, pollen size and frequency distribution of pollen grains was quantified in the progeny of this cross and the parents. A large polymorphism in pollen grain size was found within the interspecific progeny with higher production of unreduced pollen in triploids (38%) than in diploids (29%). Moreover, using PCR amplification of selected microsatellite loci, while 13.7% of the pollen grains from the diploids showed two alleles, 41.28% of the grains from the triploids amplified two alleles and 5.63% showed up to three alleles. This suggests that the larger pollen grains could correspond to diploid and, in a lower frequency, to triploid pollen. Pollen performance was also affected with lower pollen germination in the hybrid triploids than in both diploid parents. The results confirm a higher percentage of polyploids in the interspecific cross, affecting pollen grain size and pollen performance. The occurrence of unreduced gametes in A. cherimola, A. squamosa and their interspecific progeny that may result in abnormalities of ploidy such as the triploids and tetraploids observed in this study, opens an interesting opportunity to study polyploidy in Annonaceae.
(...)
Polyploidy is believed to be a major mechanism of adaptation and speciation, recognized as a major force in evolution (Van de Peer et al., 2017) and very valuable for crop improvement (Udall and Wendel, 2006; Mason, 2016). Polyploidy is more common in plants than in animals. It is estimated that between 30 and 70% of extant flowering plant species are polyploids (...)"

More I will not paste here. The best is to study the complete report by yourself!

Bytheway...to my new hybridizations of this year there is again a small setback. One of the ovaries, which took weeks to show that pollination was successful, has now decided to dry out after some growth. Another one is still in good shape, I hope it stays that way. Last year, such an ovary grew into a strongly deformed fruit, which is another sign of an unusual way of embryo formation. Unfortunately this fruit dried up in centimeter size and still hangs on the tree like a mummy. I have pictures, but I do not want to overload this post!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Ghost on September 06, 2020, 03:18:42 AM
Those plants look extremely healthy. Keep us updated! Great progress
Title: Re: Cherimoya/Pawpaw hybrid
Post by: usirius on September 06, 2020, 03:35:00 PM
Those plants look extremely healthy. Keep us updated! Great progress
Thanks for your feedback. Yes I will keep you informed as well. There would already be a lot more to tell. For example, the difference in the seedlings - this could perhaps be an indication of differences in the chromosome sets. According to the studies shown in the above-mentioned postscript that seedlings of hybrids can have different chromosome sets in different proportions,. Then I could show pictures of the seeds, which actually looked very strange. Soon I will harvest a pawpaw fruit that was pollinated with cherimoya pollen, I will definitely take pictures of the seeds and document all interesting observations about the future seedlings.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Tropical Bay Area on January 20, 2021, 01:27:17 AM
Those plants look extremely healthy. Keep us updated! Great progress
Thanks for your feedback. Yes I will keep you informed as well. There would already be a lot more to tell. For example, the difference in the seedlings - this could perhaps be an indication of differences in the chromosome sets. According to the studies shown in the above-mentioned postscript that seedlings of hybrids can have different chromosome sets in different proportions,. Then I could show pictures of the seeds, which actually looked very strange. Soon I will harvest a pawpaw fruit that was pollinated with cherimoya pollen, I will definitely take pictures of the seeds and document all interesting observations about the future seedlings.
Is this continuing? :'(
Title: Re: Cherimoya/Pawpaw hybrid
Post by: aethiopicum on January 29, 2021, 07:03:53 AM
I follow this experiment for quite some time now - really exciting! I hope there will be some updates soon. If you ever need help in growing out "hybrid" seeds or grafting them on Asimina rootstocks for faster fruit formation, please contact me. I'm from (southwest) germany as well.

Beste Grüße von der Bergstraße!
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Daintree on January 29, 2021, 10:18:10 AM
If it weren't for thousands of years of botanical experimentaion, we would all still be eating teosinte instead of sweet corn!

So have at it!!!!

Cheers,
Carolyn
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Triloba Tracker on March 30, 2021, 11:08:24 AM
usirius, any updates?

 ;D
Title: Re: Cherimoya/Pawpaw hybrid
Post by: TriangleJohn on April 04, 2021, 07:42:35 PM
Here's my years later update (see the original post). My only surviving potential pawpaw x cherimoya cross has finally bloomed and the flower looks just like a pawpaw and it bloomed at the same time as my other pawpaws. I believe the mother plant (pawpaw) may have been influenced by the presence of cherimoya pollen but that a cross never occurred. Everything about this tree has been true to pawpaw. There was no cherimoya-ness to the leaf shape, the growth style, the stem color and now the flower color and shape.

I get more fruit from the row of pawpaw trees than any normal human could eat, but neither of the two cherimoya trees have ever made a fruit. I will try to master the art of hand pollination. I hear these are difficult in Florida so my climate may have the same roadblocks (high summer heat and humidity).

The original pawpaw tree that had the one branch that bloomed in late summer, where I attempted to cross with cherimoya pollen from my greenhouse collection, that tree has been dead for a while. The branch that bloomed twice in one year eventually died and then the entire tree died.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on April 04, 2021, 10:02:48 PM
Thank you for the update, sir! 
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Perplexed on August 07, 2021, 12:54:28 AM
Any updates? Been a minute.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: TriangleJohn on August 09, 2021, 08:18:04 PM
I spoke too soon - the larger of my two cherimoyas does appear to have some fruit set. Years of hand pollinating has finally paid off. Perhaps wearing a bumblebee costume did the trick! Actually I think the tree just wanted to be of a certain size. It is seed grown and produces a lot of flowers so I get to practice often.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Polypterus on August 28, 2021, 11:13:12 AM
Have you considered grafting cherimoya onto the pawpaw x cherimoya hybrid to see if it could potentially be used as a cold hardy cherimoya rootstock?
Title: Re: Cherimoya/Pawpaw hybrid
Post by: TriangleJohn on September 19, 2021, 03:05:58 PM
I'm not sure that would work. We get really cold winter weather sometimes and I think the rootstock would be the only survivor.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Plantinyum on September 21, 2021, 08:32:45 AM
Did anyone ever tried to approach graft cherimoya and paw paw ? I am interested in this as i have some seedlings of both i would likw to wxperiment with ??
Title: Re: Cherimoya/Pawpaw hybrid
Post by: linsecte on December 11, 2021, 03:10:04 PM
I would love to sow or graft and root such an hybrid. Then compare its cold hardyness in my temperate climate spain and france to know the frost limit.
I could also share unique varieties, look the topic I did about my collection.
I'm crazy of cherimoyas, it,s my main food...
Thank you so much for this awesome réalisation
Title: Re: Cherimoya/Pawpaw hybrid
Post by: linsecte on December 11, 2021, 03:14:58 PM
Did anyone ever tried to approach graft cherimoya and paw paw ? I am interested in this as i have some seedlings of both i would likw to wxperiment with ??
Yes, but it doesn't last long. I grafted cherimoya on asimina, it growed a few months but died quickly. Other experienced the same. But an hybrid will probably be more compatible
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Fjaen on December 17, 2021, 07:27:44 AM
I have been reading this with interest, hope there is more info from Usirius.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Denis on January 08, 2022, 07:09:23 AM
I would love to sow or graft and root such an hybrid. Then compare its cold hardyness in my temperate climate spain and france to know the frost limit.
I could also share unique varieties, look the topic I did about my collection.
I'm crazy of cherimoyas, it,s my main food...
Thank you so much for this awesome réalisation

What is favorite varieties (sorts) of Annona cherimoya?
Best regards,
Denis.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: Guanabanus on January 08, 2022, 12:45:29 PM
Off topic.
Title: Re: Cherimoya/Pawpaw hybrid
Post by: dytandme on November 02, 2023, 09:06:29 AM
Has anyone got any updates?