Possibly a silly question but.

I know (for example) a diploid oriental crossed with a diploid Asiatic would require embryo rescue (or more...I know the cross exists but not being common possibly means the embryo rescue isn't as successful?)

But would the same hold true for tetraploid oriental (although not sure they exist? Can't find any named cultivars) cross tetraploid Asiatic?

From what I've read the need for embryo rescue is related to endosperm not matching up but in the case of a tetraploid cross that doesn't seem like it'd be an issue?

I realise there's a bunch of fertility issues with tetraploid not producing as much viable seed compared with diploid but that's not really what I'm trying to figure out.

Anyone able to shed any light on that, haven't been able to find anything specific on the topic.

Thank you.

Good question. Looking forward to reading some answers!

And to the forum.

I, too, am interested in this discussion and would like to know if such interdivisional crosses are easier at the 4N level. I am not aware of any tetraploid OA hybrids, but there are some tetraploid LOs, LTs, LAs and OTs I know of:

Chiara VIII LO
Easter Morn VIII LT
El Condor VIII LO
Faith VIII LA
Longicanda VIII LA
Longida VIII LA
Longiklara VIII LA
ML's Ortega VIII OT
Northern Dazzle VIII OT
Pink Champers VIII OOT
Pink Heaven VIII LO
Regal Star VIII OT
Santa Rosa VIII LO
Tanita VIII LO
Tetra Black Beauty VIII OT
Vendella VIII LO

I've been compiling a list of known ploidies here (I also list the source of my information so you can double-check it if you'd like):

Excel: https://docs.google.com/spread...
PDF: https://docs.google.com/spread...

Australis said:I, too, am interested in this discussion and would like to know if such interdivisional crosses are easier at the 4N level. I am not aware of any tetraploid OA hybrids....

Nor am I, but then I'm barely aware of OA hybrids existing given they aren't common. Its why I used it as the example, given how different they are with germination seems like a good example to see if anyone knows if the germination at tetraploid level is possible at the 4N.

Largely just curious given other polyploid crossings in other plants becoming more viable to achieve fertility and germination in their wider crosses...just seems odd that it hasn't been explored with liliums, someone surely knows something.

I have heard that there may be some ploidy studies done in the near future. Hopefully the findings will be reported in the NALS bulletin, if there are concrete findings.

Lilies are not where the money is which is why there has not been much research done in this area. Grants that cover a wide range of study areas will be the best bet for it. Here's to hoping more is discovered with tangible concrete evidence based findings.

So no one really knows yay!

On a tangent (ignoring ploidy), as I can't find anything conclusive online. Are any interdivisional hybrids possible without embryo rescue/culture? I realise there's probably always exceptions but looking for more general info. I would have thought maybe AA/asiapets would but given how they are....almost unheard of it seems possibly not. OT seems possible from some posts in the seedling thread?

Or do all interdivisionals currently require ER/C?

Anyone know with AA/Asiapets, OT, LA, OA, LO and any other cross I'm likely missing. Thank you.

A while back I came across a paper that had a list of crosses that were known to work without embryo rescue and posted it here: http://garden.org/thread/view_...

So certainly some intersectional hybrids are possible without needing special techniques (the standout in that list is L. speciosum X L. nepalense). In the majority of cases, though, my guess would be probably not.

Edited to correct interdivisional vs intersectional (thanks Leftwood).

Splitting hairs here for some people, but "Iinterdivisional" may or may not be the same as "intersectional", yet another irreconcilable difference between horticulture and botany. But I might point out that the information in the paper thatJoshua notes in the previous post is titled intrasectional, not intersectional. Intrasectional hybrids are crosses within a section (of lilies in this case); intersectional hybrids are crosses between sections, and would be more akin to interdivisional. Still, I would consider L. speciosum x L. nepalenses to be a much wider cross than a normal intrasectional hybrid.

I noticed that also (intra vs inter) but figure it may be a case that inter may not be possible without extra steps. I'd assume tetraploid would overcome that to some extent as it has in many many other plants, just can't find the info I'm looking for.

But yes interdivisional and intersectional are likely being used to mean the same thing. I'm just using division because everything I'm reading refers to the 8 (9?) divisions.

I just came across this thread - so sorry to resurrect this from the grave.

I would expect you would need to do cut-style pollination and embryo rescue to get a 4N Oriental x 4N Asiatic - same kinds of barriers exist. Added to this is the likelihood of lower fertility at the 4N level. If you pulled off the cross, there is a much better chance the off-spring would be fertile than the 2n version of the same cross. No guarantees - just talking about likelihood. I had a chance to talk about this with Bob Griesbach and he encouraged me to try things like this. A wide cross like this where plants exist is 4N Trumpets/Aurelians x 4N Asiatics. Lots of these guys floating around. Again - would likely take some special techniques but you could get some seedlings they could be fertile in the second generation and not require further fancy breeding techniques to get seed.

It's less than 6 months, I bumped something that was dead for 2 and a half years just to flesh out a mathematical technicality https://garden.org/thread/view...
so no need to apologise, I get that some topics are likely to be viewed randomly for years because of various keywords.

I agree the barriers to pollination would still be there...just not sure embryo culture would be necessary, imagine it could be significantly reduced but given full "code" is there to create viable endosperm I would think some would germinate and carry on to bulb...which isn't to say that viability from that already reduced pool would be high, just a few lucky exceptions (I like the exceptions that seem impossible)

But it goes back to not sure any 4N oriential exists, a lot of OT, few LO so it's kind of dead end on that front to begin with. It's still a worthy experiment but currently not within reach due to the missing 4N Oriental/s.

Agree there are, I found seeds of some and other tetra combinations (what's commercially available in Australia as far as tetraploids are concerned seems awfully limited...), so different approach and possibly odder experiments to come in 2 to 3 years and results in 4 to 6.



On a slight tangent. Is the fertility between a parent and child reduced or not an issue. I mean say I crossed

(this example is 4n asiatic but not really relevant to my question...although if there is a difference at 4n and 2n then feel free to mention it, more info never hurts)
Tresor x Red Velvet and got seedling A
Would
A x Red Velvet
have potential incompatibility issues?

I don't imagine it would because species and strains exist and often those involve some degree of sibling seedlings crossing but I personally don't know the answer, just assuming.

Protoavis,

I am not a PhD botanist and I will share what I think based on what I have read and the opinions I formed on this. When a flower is pollinated and an egg fertilized there is actually two fertilizations that happen (see uploaded image with brief description).



The first forms the embryo and the second forms the endosperm. In diploid Lilium the more straight forward one is actually the embryo (2n) and endosperm (5n) is more complicated and this is why I believe embryo rescue is needed to facilitate most wide crosses. Take this to the tetraploid level and things could be more complicated yet as the embryo would be 4n and the endosperm 10n. I am not speaking from experience with this as I haven't done any of these crosses yet, just looking at the process and assessing. In the end, we just need to try the crosses and see what happens. Leslie Woodriff made the Black Beauty cross without cut style or embryo rescue. It is all a numbers game and if you make enough crosses at some point you will win the lottery. I am set up to do embryo rescue and did a little bit this past autumn. I decided based on the look and feel of the pods that formed what I would do it on - I didn't do it on everything. There are some crosses that you learn from experience (Silk Road for example makes a normal seed for me with 4N OT pollen) don't need it and when you open the first pod and find a bunch of near normal seed then you let the rest of the pods ripen normally.

In the USA there are many commercially available 4N Trumpets & 4N Asiatics so anyone here that decides they want to try this can get material to start without too much difficulty. There are many seeds in the NALS seed exchange for both types also which will take a few more years but you can raise your own if you can't get bulbs.

There has been lots of research done on which way to do wide crosses and they have found some groups are more likely to be successful as the pod parent than others (not that it can't work both ways). So for the AT's, I believe the recommendation is to have the pod parent be from the trumpet/Aurelian group. This works to our advantage as the Asiatics usually bloom before the trumpet/Aurelians so it is really easy to save pollen. I would recommend using cut style pollination (easy to do - no special equipment needed) and see what you get. You might get some normal seed from this and then you are off and running.

As for 4N Orientals - there are none commercially available here in the USA. There are a number of research articles from the Dutch breeders that show they have them in the breeding programs but they don't get released for commercial production. So the answer is we have to make our own. One thing I noticed is that in the past, several breeders converted Orientals to 4N and the first thing they do is cross them onto OT's. Why didn't anyone intercross these 4N Orientals to get seed? I think the only way we are going to get sustainable 4N Orientals is to convert several and intercross them to create seed strains.

On your other point - I don't think the fertility of a parent x child is reduced. It is not about fertility but vigor. Crossing repeatedly back to a parent is actually a breeding strategy some will use for various purposes. But we are not talking about wide crosses here - just crosses within a "normal" breeding group like Asiatics. By the way, my experience with Red Velvet is that it is a triploid and I have not been able to get seed from it. I have not tried it as a pollen parent, but have tried many crosses onto it with 4N Asiatic pollen. I am not saying you can't use this as a parent but the odds of getting seed are extremely low.

Regards,
Patrick

Australis said:I, too, am interested in this discussion and would like to know if such interdivisional crosses are easier at the 4N level. I am not aware of any tetraploid OA hybrids, but there are some tetraploid LOs, LTs, LAs and OTs I know of:

I've been compiling a list of known ploidies here (I also list the source of my information so you can double-check it if you'd like):

Excel: https://docs.google.com/spread...
PDF: https://docs.google.com/spread...

Joshua,

I looked at your file and there are some things in it that aren't consistent with other information I have seen. Some of the items listed as 4N I have seen reference that they are 3N. The other thing to consider is that a number of the OT's out there as 4N are OTTT - Leslie Woodriff for example. A few like Arabesque & Scarlet Delight are OOOT's. My point in mentioning this as it gives some indication as to what might be more likely to set seed on that plant. Also for the LO's & OT's - many of the newer Dutch cultivars are triploids - LLO, LOO, & OOT's. For the OT's I have heard from a number of people they have some fertility and I was able to get some seed from them when crossed with 4N OT's. The most recent NALS yearbook has an article that discusses that using 3N's like this as a pod parent leads to mostly aneuploidy (number of chromosomes is in not increments of 12 but is too few or a few extra) seedlings - some of these seedlings can be fertile but now things get really strange.

Regards,
Patrick

Hi Patrick,

Thanks for the comments. I am quite happy to take corrections and I put the sources of my information there so that others could see it and decide how much weight to give it.

I am aware that there is a lot of conflicting information over the ploidy of 'Red Velvet'. The RHS registry supplement 4 does say it is 4N, so considering that is a relatively recent update, I took that as my primary source.

If you have the time, I would be very interested in anything you can add to/correct on my list.

Kind Regards,
Joshua.

I was just looking at your list and I think Gran pardiso was 4n, it was fertile I got several seedling from it over the years, the best were seedlings using Bel Ami as the pollen parent:








GPXBA RED FROST CLS.jpg

And I got a nice seedling using my 4n Firetruck as pollen parent