My new azalea cultivar

[barrosinc]

how long does it take or a to hybridize an azalea and for it to flower?

 

[Harunobu]

Maybe in 3 years in zone 9 if you are lucky. I think I get first flowers in 4 years. If you have a sporting satsuki, you really need a larger plant with more flowers to notice how it sports. So add 2 to 3 more years. If plants are really leggy and struggling, it could take some more years. But then you might want to compost it anyway. You kind of know what you have after two flowering seasons. So in zone 9 in 5 years you definitely know if you got a nice plant and you can enjoy the fruit of your labour.

I obtained a new plant today that I am quite excited about, and it is not a satsuki. Of course I am looking for new and different ways to hybridize than the Japanese breeders. So I look at both worlds. This year, a new plant was released by a well-known Germany breeder family business Hachmann called 'Wischiwaschi':


This thing now has a huge family tree with al kinds of different azalea from all across the world:

Bundessortenamt: Deutsche Genbank Rhododendron

Deutsche Genbank Rhododendron

www.bundessortenamt.de

I don't even know any satsuki with a family tree documented that deep and that well.

And it turns out the plant itself is an almost-white with a dark blotch. And tested winter hardy in the colder parts of Germany (they report -22 C). So this is the perfect canvas for me to breed with satsuki.
Where I used 'Alexander', R.nakaharae with the satsuki Kinsai, this plant has R.nakharae crossed with Gumpo (by the same guy) as a parent.
On the other side of the family tree, they used 'Maischnee', which is basically the most refined Germany style kurume-type garden azalea the Hachmann's produced up to that point. And they crossed it with a very hardy large flowering azalea from the Czech Republic (possibly zone 5 hardy).
Maischnee has as parents some azalea you other azalea people know very well, like Mother's Day, Kermesinum and Rosebud, etc.
So 'Wischiwaschi' is basically a Gumpo with European hardiness and apparently recessive R.nakaharae genes for small narrow leaves.

I added up the percentages as:
R.tamurae 25.00 (same as maruba satsuki or R.eriocarpum)
R.nakaharae 25.00
R.yedoense var. poukhanense 17.97
R.mucronatum 15.63
R.kiusianum 5.86
unknown 4.69
R.kaempferi 2.34
R.simsii 1.95
R.indicum 1.56

So this azalea seems perfect for crossing with the somewhat somewhat inbred heavy R.indicum-style satsuki. I expect this azalea crossed with any satsuki to immediately give some nice results.

Turns out it also produces lots and lots of pollen.

I kinda hope the same guy in 10 years won't release a bunch of satsuki crossed with European azalea that are all way way nicer than mine. If they made this cross 15 years ago, what do they have in the pipe now? I can't compete with a professional family business who have been doing this for almost a century now.

 

[NOZZLE HEAD]

I think considering polyploidy in azaleas is an excellent point. Turns out several satsuki cultivar are already polyploid. Haru no Sono/Issho no Haru and Suisen and sports being prime examples. You can notice the petals are just fatter, which has all kinds of advantages. It seems to me that tetraploid azaleas are superior in every respect. Triploid azaleas seem to look similar, but they have fertility problems. Pretty sure many Robin Hill azalea have the same properties. But I don't think anyone tested those.

I highly considered using tetraploid satsuki as often as possible for better results. But inducing it myself, no. It has been tried successfully in the past. But one kinda has to wonder why we don't take every existing cultivar, turn it into a polyploid with oryzalin or colchicine, and forget about the old diploid version. Not entirely sure why.

There are of course some practical problems. Do do it properly, you need to check the ploidy. I never used flow cytometry myself, in my research, but when it came up someone always mentioned that it was too expensive and there was a machine somewhere, but a long waiting list as well. I should have the skills to take growing tips of my azalea, use a chromosome dye, and use a microscope to count the individual chromosomes. At this point in my career, not sure how to arrange the kit.

On top of that, if I wanted to induce it, it seems I still need to do some tissue culture on azalea in a oryzalin bath. And something that messes with microtubili in plants so to prevent chromosome segregation is still toxic.

Maybe the most practical way would be to soak seeds in a solution of oryzalin just as you sow them. But it would be nice to be somehow able to check what you are doing. The seeds may already be triploid, for example. And then the plant looks triploid, and you think your method works. And it doesn't look like this stuff is for sale in the EU to consumers. Making a 0.002% solution of something only classified as a 'irritant' and 'environmental hazard' doesn't sound super dangerous. But anything that messed with DNA in some way, don't mess with it unless you know exactly what you are doing.

Well, some googling and I learned today that they trialed colchicine as a drug against covid19. And that there are people growing cannabis plants that try to create polyploid plants by trying to extract colchicine from crocus bulbs, warning the reader of the article that colchicine is extremely toxic, but here go try this anyway.

This is a link to the plant breeder at OSU who has done a lot of oryzalin work.

Ryan Contreras

horticulture.oregonstate.edu

His main method is spraying seedlings with 100ppm oryzalin just before the first true leaves emerge, but his ornamental breeding program does a lot of research.

I recall that some other breeders when I worked at the university did some low concentration TC stuff and seed soak stuff with oryzalin and were unhappy with the results compared to colchicine.

 

[Forsoothe!]

[QUOTE="I can't compete with a professional family business who have been doing this for almost a century now.
[/QUOTE]
Not so! There is still a lot of variability in outcomes crossing a cluster of flowers on one plant with a single pollen from another plant. If you get fifty seeds from the exactly the same cross, you still get lots of slightly different siblings. Lady Luck can smile on you, anytime. It's why you play the game.

 

[Harunobu]

You are right. And this isn't a competition anyway, of course. I have plants and I am happy.

So a few more 'Alexander' crossed with 'Hekisui':

Axe-10-07

This one has the same foliage as most of them, but this flower is different from all the others. It is more rounded with petal overlap and the colour is peach.

Axe-10-10

Has the largest (orange-) red flower of my Axe seedlings. Also the most creeping, which makes it hard to take a picture that is in focus with my phone. This one now has more space to grow, so maybe it will stop trying to grow below and underneath other azaleas. Tempted to bin this one.

Axe-10-16

Kind of an intermediate of 08 and 04 from previous posts. Hard to differentiate all of these. I was surprised it kinda looks so nice in this picture. It is in a shaded spot so blooming even later so these flowers are just opening. Picture was taken after two days of rain, and these flowers look unblemished. Just awkward, but kinda cute, as they are almost done fully extending.

Axe-10-18

Same plant habit as most others, but this one has very ordinary-looking purple flowers that so far don't quite come out nicely.

Axe-10-21

The largest flowers of all Axe seedlings. I had some plants that were similar but with paler purple or smaller flowers and those were eliminated 2 years ago.
This one had the most dark green winter foliage of all..
Very robust plant and flowers. But the flowers kinda hang down because of the length of the stem and the size of the flower. Transplanted it to give it more space. Maybe that will help it become a better push that better projects these flowers.
Not what I am looking for, but decent enough to keep around, for now.

 

[Harunobu]

MxK-12-03

This cross of 'Mary Helen' with 'Kozan' was mentioned in the earlier post about the 01 sibling seedling. At this point, this 03 is actually my favourite. As mentioned, I like the foliage a lot more as it looks like more regular satsuki-type foliage, and actually different from both it's parents (it actually has the round maruba-satsuki type leaves, like it's grandparent 'Kagetsu'). But the flowers also seem more long lasting than 01 as well. Rain also did not really diminish or blemish them. Now that all of them are opened up, I actually like the look of this plant a lot more. And it turned out that the blotch that made 01 interesting actually faded quite quickly (not uncommon for the intensity of the blotch to diminish over time).

The 5-petal is more common than the 6-petal:

Earlier picture as of the foliage as the first flower was about to open:


Basically, just a solid white-flowering satsuki-type azalea. Nothing special. But nothing to really complain about either. I like it way better than 'Mary Helen', but a faster grower like 'Mary Helen' is probably more profitable for the nursery industry. I don't owe any classic white satsuki like 'Hakatajiro' or 'Daisetsuzan', so I don't know how it compares. I don't see any reason to use this plant as a parent in future crosses. I suspect that in the long run I will have a whole bunch of these solid but unremarkable white azalea. This feels like a plant to give away rather than bin or register. And then if some horror winter does hit and kills all my satsuki, and this one happened to have survived, I can always use it in future crosses from that point onward.

 

[Harunobu]

As-12-04


This is my largest 'Asahi no Izumi' seedling. It just grows very well and very robust. The flowers are a very pleasant round petal shape, and plenty of them. It sports a very pale pink. I have seen some tamafu/jewel spot patterns in the past. But not this year. This is the same plant as the first picture in this thread, and that picture was quite photogenic. I was quite happy with that plant back then. But the range of sports has not increased. I hoped it would throw more patterns and definitely also more intensely coloured ones. Doesn't seem that it will do this for me. Still, maybe the best sporting satsuki I grew from seed so far. So I will keep this until I have many that are better, and I might keep it then because of nostalgia. I rooted a bunch of cuttings, but maybe that's kind of pointless now since this one barely isn't good enough. I am considering using it as a parent in future crosses.
And this year, after only one day of rain, many flowers got brown spots. Not really what you want on a white flower that only sports a pale shade of pink.



I really still thing this flower shape is the best. In these pictures, the petals aren't fully extended yet, but in the picture from the OP, they are. So close to having an awesome plant. I still think this thing is great if you are in Europe and starting out with bonsai and you want to grow something from a cutting that fattens up fast, backbuds well, has small blooms that do sport to some extend. It grows way way faster than Kozan. So more like Hanabin. but I did no pruning at all and I have a dome shape that touches the soil without any empty spots or spaces. I really need to prune this thing this year. (And I actually made a mistake in misnaming these, as these seeds germinated in 2014, not 2012. So this plant now is 5 and a half years old. It is overtaking in size nursery plants I bought in 2012, that came in 20cm diameter pots. So all these are actually As-14-xx). Maybe this plant will at some point throw a sport that can be more intensely coloured? One can dream, right?


As-12-10


Another Asahi no Izumi seedling from the same batch. This one had some more problems getting large. It always had a few white flowers. But this year, it had quite a few more, and it is picking off growing well now. The flowers are kinda more cream than white. And this year, I have one flower that is sporting purplish-red. So this seedling has some potential to overtake As-12-04 as my favourite. These flowers are bigger and more wavy than As-12-04 as well. But these are not fully opened yet. Not quite sure what other cultivar they remind me off. So it is less similar to Asahi no Izumi itself. Just posting this now before it starts raining for a week. In the next few years, I have good hopes that this one will start throwing the fukurin/jewel border pattern, when this colour sport expands across the entire flower.

 

[Forsoothe!]

As-12-04
View attachment 308557

This is my largest 'Asahi no Izumi' seedling. It just grows very well and very robust. The flowers are a very pleasant round petal shape, and plenty of them. It sports a very pale pink. I have seen some tamafu/jewel spot patterns in the past. But not this year. This is the same plant as the first picture in this thread, and that picture was quite photogenic. I was quite happy with that plant back then. But the range of sports has not increased. I hoped it would throw more patterns and definitely also more intensely coloured ones. Doesn't seem that it will do this for me. Still, maybe the best sporting satsuki I grew from seed so far. So I will keep this until I have many that are better, and I might keep it then because of nostalgia. I rooted a bunch of cuttings, but maybe that's kind of pointless now since this one barely isn't good enough. I am considering using it as a parent in future crosses.
And this year, after only one day of rain, many flowers got brown spots. Not really what you want on a white flower that only sports a pale shade of pink.

View attachment 308559

I really still thing this flower shape is the best. In these pictures, the petals aren't fully extended yet, but in the picture from the OP, they are. So close to having an awesome plant. I still think this thing is great if you are in Europe and starting out with bonsai and you want to grow something from a cutting that fattens up fast, backbuds well, has small blooms that do sport to some extend. It grows way way faster than Kozan. So more like Hanabin. but I did no pruning at all and I have a dome shape that touches the soil without any empty spots or spaces. I really need to prune this thing this year. (And I actually made a mistake in misnaming these, as these seeds germinated in 2014, not 2012. So this plant now is 5 and a half years old. It is overtaking in size nursery plants I bought in 2012, that came in 20cm diameter pots. So all these are actually As-14-xx). Maybe this plant will at some point throw a sport that can be more intensely coloured? One can dream, right?


As-12-10
View attachment 308556

Another Asahi no Izumi seedling from the same batch. This one had some more problems getting large. It always had a few white flowers. But this year, it had quite a few more, and it is picking off growing well now. The flowers are kinda more cream than white. And this year, I have one flower that is sporting purplish-red. So this seedling has some potential to overtake As-12-04 as my favourite. These flowers are bigger and more wavy than As-12-04 as well. But these are not fully opened yet. Not quite sure what other cultivar they remind me off. So it is less similar to Asahi no Izumi itself. Just posting this now before it starts raining for a week. In the next few years, I have good hopes that this one will start throwing the fukurin/jewel border pattern, when this colour sport expands across the entire flower.

You are using the term "sport" different flowers differently than I am used to in Hosta culture. When we say a Hosta is a sport, we refer to a division or eye that is different in some genetic way from the rhizome from which it arose. It is different because there has been a spontaneous genetic change in that eye in the dividion of the first cell which continued-on, thereafter. While it is still attached to the parent rhizome, it is a separate plant and will not "revert" or change genetically. It may look slightly differently as it matures in the first five years, the changes are minor other than the size of the clump and leaves. Can you explain the process in Azalea as you are referring to it? Thanks.

 

[Harunobu]

Yes, it is a sport because it is a spontaneous genetic mutation, almost certainly a transposable element removing itself from a gene coding for a pigment enzyme. Once the transposon is gone, the pigment synthesis pathway is restored, and pigment is created in those cells, and all other cells that originate from the cell where this transposable element first came from. So the red sector shows you how the petal grew. The mutation occurred early on, so the red sector goes all the way from the center outward to the edge. You can see that near the edge, it becomes white again. This is because of location, not genetics. Azalea flowers can also do a fukurin/jewel border pattern. And here, pigment is somehow turned off at the edges of the petals. The cells somehow know not to produce pigments, because they are at the edge, in the same way as leaf cells know not to produce flower pigments, because they are leaf cells and not petal cells.

Now, you can only see this sport in the petals, because only there the genotype translates to a distinct phenotype. But if you imagine a magic lens that allowed you to see this specific genetic variation, these streaks would occur all over the plant, in any tissue. And even in this flower, you can imagine that a similar streak of the red genotype occurs in the ovule. So this specific flower may have a number of gametes where the red pigment pathway is functional, exactly where this red streak in the petals originate. And if such a gamete is fertilized by a white pollen cell, the result could be a plant entirely with the fukurin/jewel border pattern, like the azalea 'Ben Morrison'.

https://flic.kr/p/rsJcKN
There would be a second mutation possible to turn the jewel border pattern into a fully solid one. So the bicolour effect in 'Ben Morrison' (or Nyohozan) is not the result of a genetic mutation, thus not a sport. It is a positional effect

So yes, in my flower it is a chimeric effect, Rather than rely on a mutation in a gamete, an alternative would be to take the red part of the petals, do tissue culture on it, make stem cells, and grow new plants from that. They would be like 'Ben Morrison'. But in 'Ben Morrison' the white petals and the coloured petals are not chimeric because they have the same genotype. Which is why the pattern is positional rather than dictated by cell lineage/growth pattern. Similarly, if this sport occurs in a new shoot, and that shoot develops into an entire branch, all flowers on that branch of my azalea would be the fukurin/jewel border bicolour pattern. And taking a cutting from that branch would give you a new cultivar, similar to Ben Morrison. And you could register this as a new cultivar. And that would then be the fukurin/jewel border sport of As-12-10.

A somewhat older but review paper on this would be:

https://journals.ashs.org/hortsci/view/journals/hortsci/32/5/article-p773.pdf

Not familiar with hosta's, but a quick google picture shows that their leaves have different colour in the center and at the edges. Such a leaf variegation likely is not a mutation, for the same reason as why Ben Morrison is not a mutation. But like in my azalea, you could have both. A mutation could turn on and turn on a positional difference. Because the edge of my flower, where the red changes back to white, that you can map exactly onto the edge of 'Ben Morrison'. Not sure what you mean with 'eye' and how the rhizome is relevant. You take cuttings from roots?

 

[Forsoothe!]

Yes, it is a sport because it is a spontaneous genetic mutation, almost certainly a transposable element removing itself from a gene coding for a pigment enzyme. Once the transposon is gone, the pigment synthesis pathway is restored, and pigment is created in those cells, and all other cells that originate from the cell where this transposable element first came from. So the red sector shows you how the petal grew. The mutation occurred early on, so the red sector goes all the way from the center outward to the edge. You can see that near the edge, it becomes white again. This is because of location, not genetics. Azalea flowers can also do a fukurin/jewel border pattern. And here, pigment is somehow turned off at the edges of the petals. The cells somehow know not to produce pigments, because they are at the edge, in the same way as leaf cells know not to produce flower pigments, because they are leaf cells and not petal cells.

Now, you can only see this sport in the petals, because only there the genotype translates to a distinct phenotype. But if you imagine a magic lens that allowed you to see this specific genetic variation, these streaks would occur all over the plant, in any tissue. And even in this flower, you can imagine that a similar streak of the red genotype occurs in the ovule. So this specific flower may have a number of gametes where the red pigment pathway is functional, exactly where this red streak in the petals originate. And if such a gamete is fertilized by a white pollen cell, the result could be a plant entirely with the fukurin/jewel border pattern, like the azalea 'Ben Morrison'.

https://flic.kr/p/rsJcKN
There would be a second mutation possible to turn the jewel border pattern into a fully solid one. So the bicolour effect in 'Ben Morrison' (or Nyohozan) is not the result of a genetic mutation, thus not a sport. It is a positional effect

So yes, in my flower it is a chimeric effect, Rather than rely on a mutation in a gamete, an alternative would be to take the red part of the petals, do tissue culture on it, make stem cells, and grow new plants from that. They would be like 'Ben Morrison'. But in 'Ben Morrison' the white petals and the coloured petals are not chimeric because they have the same genotype. Which is why the pattern is positional rather than dictated by cell lineage/growth pattern. Similarly, if this sport occurs in a new shoot, and that shoot develops into an entire branch, all flowers on that branch of my azalea would be the fukurin/jewel border bicolour pattern. And taking a cutting from that branch would give you a new cultivar, similar to Ben Morrison. And you could register this as a new cultivar. And that would then be the fukurin/jewel border sport of As-12-10.

A somewhat older but review paper on this would be:

https://journals.ashs.org/hortsci/view/journals/hortsci/32/5/article-p773.pdf

Not familiar with hosta's, but a quick google picture shows that their leaves have different colour in the center and at the edges. Such a leaf variegation likely is not a mutation, for the same reason as why Ben Morrison is not a mutation. But like in my azalea, you could have both. A mutation could turn on and turn on a positional difference. Because the edge of my flower, where the red changes back to white, that you can map exactly onto the edge of 'Ben Morrison'. Not sure what you mean with 'eye' and how the rhizome is relevant. You take cuttings from roots?

This is going to be a difficult discussion for me because I am not up to your level of science, but I'll try. Hosta sport via a genetic change at the time of cell division when a new bud forms on the side of a crown (some Hosta are rhizomatous, some are not). The bud matures into an eye or single crown which may stay attached or be separated by breaking or cutting off becoming a separate plant. Crossing different species or varieties can also create new cultivars. Species will breed true, for the most part, but cultivars only seem to breed true by luck, and only rarely. All species are fertile, but cultivars vary in fertility wildly from totally fertile as pod and pollen parent to totally infertile, and everything inbetween. Seeds can be treated with microwaves or chemicals to alter genetics, and so can the buds taken from the sides of crowns as long as the bud has one piece of root connected. (Buds are usually sliced longitudinally for chemical penitration of the meristem tissue.) Tissue culture is done by slicing the eye (with a piece of root connected). Many new cultivars come from tissue culture as off-types with the sky's the limit on variation and many of the flops (opposite variegation) coming from tissue culture.

Almost all seed-produced crosses that result in variegated scion come from a variegated pod parent, streaked being most productive and center variegated second. It's almost impossible to have variegated seedlings with any other pod leaf coloration.

The exact number of species is unknown because Hosta was introduced into Germany ~1820 or so, from Japan as Funkia, and it is uncertain whether or not some are creations of crosses or if they were the last of some species no longer found in the wild. They are mostly Japanese, with one species from China and lately a few more from Korea and the islands between korea and Japan. There are some important cultivars from an American in the 1950's and an Englishman in the 1960's and no record exist of what species were used to create those, either. Someday someone will put together a genetic trail, but right now there's lots of mystery. All of this is probably pretty similar to Azalea history and method.

There has been discussion (by better men than me) that all Hosta may have all the genes necessary to have all the characteristics displayed by all the species and cultivars and that the characteristics are changed by just turning off some genes and turning on others rather than missing some genes or by adding or combining others. Intreguing. That seems like what you are saying about your flower pattern colors? Polyploidy muddies the water.

 

[Harunobu]

Ah, so a mutation in a hosta cell can occur, and that will change what kind of positional variegation you get? And if you propagate a plant from tissue with this mutation, or either a complete new plant through budding off of the rhizosome?

I am not entirely sure how leaves become variegated. They are green because of chlorophyll. So a white or pale green variegation would mean less chloroplasts in those cells at that position of the leaf? There are also a few azalea with variegated leaves. I don't like it. Also because theoretically, it should weaken the plant and make it less efficient. And I think people report on that they don't think the variegated azalea are as robust. I do like the look of it on hosta, though.

It seems so far to me that all these colour variations in azalea flowers is just a failure of the normal patterning behavior. Apparently, insects prefer a solid coloured azalea with a blotch on the upper petal. I mean, flower shape and colour is largely a product of selection by the pollinator. It's almost a kind of artificial sexual selection for say a peacock's tail. And then it turns off that mutations can turn off and turn back on the colour of the petal. I don't really know of any azalea where the blotch turns off completely. Let alone turn back on. Maybe there is a redundant set of genes for this, so no mutation can result in a blotch-less phenotype.

And then there are these patterns that we don't fully understand or how they relate to the natural flower pattern. The capacity for humans to select, or 'engineer', a completely new regulatory mechanism, rather than just breaking/disabling something, just through centuries of plant breeding and election of specific cultivar, would be really interesting to find out scientifically.

Either way, be it pigment or chlorophyll, there is the presence of the functional gene. And then there is the expression of that gene. A mutation can also downregulate the expression of an otherwise perfectly functional gene. And there are different ways to up or down-regulate things, that cells naturally use for all kinds of things. For example, when colour gradually fades based on position in the petal, then likely one of the pigment enzymes is being down-regulated more and more as the flower gets paler. One mechanisms studies in petunia found an mRNA interference method. So the gene is there and is functional, it is expressed, but the mRNA is blocked and broken down before it is can be read and turned into the pigment-producing enzyme.

Since chlorophyll is plays such an important and universal role in all plants, the richness in regulating chlorophyll or chloroplasts must be vastly more rich and therefore more complex. And there must be something about hosta's specifically that make them prone to leaf variegation.

 

[Forsoothe!]

Ah, so a mutation in a hosta cell can occur, and that will change what kind of positional variegation you get? And if you propagate a plant from tissue with this mutation, or either a complete new plant through budding off of the rhizosome?

Yes.

I am not entirely sure how leaves become variegated. They are green because of chlorophyll. So a white or pale green variegation would mean less chloroplasts in those cells at that position of the leaf?

Yes, the density of chloroplasts in the leaf determines how much the yellow pigment will be overcome (if present), except in cells with little or none of the yellow pigment or chloroplasts which results white. The white portion is parasitic on the plant and is subject to necrosis in direct sun. The higher the density of chloroplasts, the darker the color from white to light yellow, yellow, gold, chartreuse, apple green, green, dark green and blue which is the result of having a heavy wax on the green leaf that wears off by late summer or autumn. Some Hosta also have red pigment present, usually ephemeral in spring until overcome by chloroplasts density. That red pigment probably contributes to the darkest green coloration.

Streaked Hosta are not stable and may evolve to any pattern or color over any time period from days to years. They are the best for breeding as pod or pollen parents.

Since chlorophyll is plays such an important and universal role in all plants, the richness in regulating chlorophyll or chloroplasts must be vastly more rich and therefore more complex. And there must be something about hosta's specifically that make them prone to leaf variegation.

Yes, we don't understand why Hosta are so unstable. We are really happy that they are because we have 5,000+ registered variations on the theme that we wouldn't have if they were stable. Is instability an aid to the adaptability and survival strategy of a genus, or the opposite?

 

[Arlithrien]

This is so cool. Been wanting to do this with Japanese maples for a while. Just need to get my hands on the right material...

 

[Harunobu]

After this post, it probably will take a few years before I have another post to make. There is maybe 1 or two plants on which I could do a post next year. But here an example of what can happen when a plant doesn't quite turn out so well.

HS-14-01
This is the only seedling from Haru no Sono (sport of Issho no Haru) I was able to get to flowering. Haru no Sono is one of the nicest azaleas I know. The flowers are so thick and crispy and the patterns and colours are really nice. They also last quite a long time. Besides that, it has dark foliage, which is quite attractive. It is a triploid, so everything about it is a bit bigger than usual for an azalea. But that's a common trait among the larger flowering satsuki. The seeds from Haru no Sono usually do not germinate at all. I discussed this plant with someone who had tried to germinate tens of thousands of Haru no Sono seeds. So after the first year, I got zero to germinate. The year following, I just pollinated every flower on it, not recrding the pollen parent at all, and sowed all those seeds completely covering the entire surface of a tray of sphagnum moss. I only got a couple of seedlings to germinate .These seedlings all had chlorosis. Not sure if that was because of their genes or bad care. After planting them in the garden, all but one died.
So there is only 01. This plant is healthy now, dark green like Haru no Sono, and growing well. Except, it never flowered for me, until this year. In the past, all flower buds would be dead and dried up rather than swelling. But this year, not all dried up and some opened. Sadly, the first ones were too tiny and their shape was out of proportion. Not good, but not extremely unusual for the first flower opening to be odd. Then, proper flowers did open:



Most flowers are white, one was purple, and this one had a streak. This one is dirty from the rain, but you can also see it is a bit ruffled. And these flowers last very short. Several of them dried up from the center within two days:



In fact, I have a 2 day older picture of that purple-streaked flower. And those brown markings weren't there 2 days ago. Only those small brown round speckles are mud. This flower will likely look brown and shrived up two days from now as well.

After all that work, quite disappointing! This may explain why there are almost no registered cultivar with Haru no Sono/Issho no Haru as their parents, despite them being old and very respected cultivar. I will be moving this plant to a sunnier spot, but likely it is bad genes.
It may be that there are better odds getting seeds from this flower rather than from Haru no Sono itself. Not sure if I should keep trying. It is definitely possible to get good plants from Haru no Sono eventually. Many people attempted, but no one really got plants just as nice, but different, from Haru no Sono. Maybe other plants will give me good results much easier.

@Arlithrien
I remember considering collecting maple seeds the first year I was thinking about planning to grow plants from seeds. I actually started out with chili peppers initually Then I found bonsai to be interesting and found maples and azaleas. Kinda glad now I picked azaleas and not maples though

 

[Leo in N E Illinois]

When working with polyploids, sterility is a frequent roadblock. Not that they are 100% sterile, but they tend to have a low fertility rate. And the few survivors tend to be aneuploids, uneven, partial or incomplete sets of chromosomes. But once in a while, maybe 1 in 10,000 one gets a true amphidiploid, a plant with an even ploidy number, 4N or 6N or 8N, and all paired up in such a way that it is a reconstituted, fully functioning genome. This plant will also be fertile, and this fertility can carry on a few generations. Rare, but it does happen. Makes it worth trying over and over again.

 

[Harunobu]

Yes. The paper I linked earlier shows evidence that all 3n azalea are male infertile. Their triploid plants do cross as seed parents with both 2n and 4n pollen parents. The paper does mention Issho no Haru but sadly only as a pollen parent, and it is infertile.

I tried pollinating with both 2n and 4n and I didn't see a difference. Then I just stopped labeling, because I couldn't expect them to germinate.

I spoke with Joe Klimavicz and he has quite a few Haru no Sono seedlings, and many of them are fertile I think. He did quite a huge effort, but none of his registered plants have Haru no Sono in their parentage. None of the children or grandchildren were as good as Haru no Sono. It is the triploid plants that are the problem. 2n or 4n and that seems fine. The paper I linked did not test the germination rate of the seeds from 3n plants. Only if they had the correct shape or not. I think they postulate that 2n x 4n gives you the 3n. Their evidence is that they have a few parent-child relationships in the azalea they selected to have their ploidity tested. They didn't grow any seedlings themselves and test those to confirm this. They do state that polyploids can form asymmetric gametes. So I guess if a 3n cell undergoes meiosis, some chromosomes are doubled, but others are not? I do know that Klimavicz noted that his Haru no Sono seedlings have thick petals and other features suggesting ploidity. Certainly this suggests triploids don't produce straightforward 1n gametes. If they did, why would there be a fertility issue?

So yeah, if you try enough times, maybe you get female gametes in Haru no Sono that are 2n or close to 2n, and you get a proper 3n or 4n seedling, depending on if you use a diploid or not as pollen parent. But if meiosis goes messy because of the triploid nature, you get a mess and the seed doesn't fertilize.

So since I have Suisen and Miharu, which are actually mixoploids with 2n gametes, so they reproduse as tetraploids, this will have less issues. Which is further established by the 40+ or more cultivar registered with Suisen as a parent (male and female).

And this is only true for evergreen azalea. In deciduous, apparently there is already some differences. But it can be as simple as the polyploid pollen grain being too big to make a pollen tube on diploids.

 

[Pitoon]

OK, next question is.....can azalea pollen from plants that bloom early be stored for plants that bloom later to cross pollinate?

 

[Harunobu]

Yes, but I don't the fine details as I have never tried. It is even possible to store pollen from plants that bloom late for the 10 months of so. But then you have to desiccate and store in a fridge.

I have not tried storing pollen myself. So I do not know how viable it will stay at room temperature or at room humidity. So you probably want to store pollen for 1 to 3 weeks? I would just try it at room temperature and keep it inside. If that doesn't work. store it mixed with a desiccant at room temperature. If that doesn't work. Freeze it fro those weeks mixed with a desiccant.

An alternative could be to put the early bloomer in a pot and keep it in the shade and hope that slows it down.

 

[Forsoothe!]

You can save Hosta pollen in a freezer. They bloom over a 4 month period from mid June to mid October. They need to be protected from freezer burn, but if they are in a 5 gram pot placed in a normal compartment of a typical plastic organizer tray you can just lay the filament in the pot which has a screw lid and they last as least a year. I've been told the pollen (of Hosta) will last longer than one year.

 

[Leo in N E Illinois]

I've saved pollen of orchids in the refrigerator for 14 months and successfully got seedlings. Put fresh pollen on a folded piece of wax paper. Store dry in refrigerator.