Rosa roxiburghii hybrids...

Rose Genetics Ploidy Level
, , , , , , , , , , , , , , , , , , , , , , ,
1

So, I am stumped as to what to think about these hybrids that are mostly red polyantha x Rosa roxiburghii. Theyre all orange-red, repeat blooming poly-flora types. Theyre fertile. They show no species trait. And theyre from knowledgeable breeders. Examples: Floradora, Cinnabar,

And then we have roses like Bonica x Rosa roxiburghii, which yielded Schweizer Garten and Dietrich Woessner. Theyre cream landscape shrubs similar to Bonica. Again, they dont show any species traits. However, they look remarkedly superior to all of the Bonica selfs I have seen.

The reason I am curious is that I do not know how to properly label my own seedling. A few years ago I did Belle Epoque x Rosa primula. Rosa primula is the closest relation to Rosa roxiburghii that I know of. BE was the only rose blooming at the time because it was raining (yay for Oregon hybridizing in May…). The male reproductive parts that I removed were not viable because it was too cool, and I made sure that I was thorough. About 5 seeds germinated from this cross. All died, except one, from what looked like genetic incompatibility. It was extremely vigorous and kinda fuzzy lol. Well, it lost that fuzz and bloomed that spring! And it looked nothing like a species whatsoever. I was oh so very confused. The thing is, though, that it matured into a definite floribunda. It is distinctly different than Belle Epoque.

It matured to about 3’ x 3’. It blooms in definite clusters. It retained similar foliage, but it is smaller and more compact. It smells fruitier. It roots with ease. The color is similar but way different. BE is a reverse bicolor whereas the seedling, which I call Belle Belle, is a reverse bicolor and a phototropic blend. Also, it doesnt turn ghostly colors in the heat like BE. They start out apricot orange with a rust red reverse, but the sun will cause the petal face to become more and more orange and rust red. It is quite the cool effect. It is nothing that I would expect from an HT self, even a weird one like Belle Epoque.

So, I doubt it is a self. I am not sure if the other examples are selfs either. What I am wondering is if the female is accepting the pollen as sterile to it and then doubling the egg.

What do you all think?

Also, note that the roses that are diploid rugosa hybrids with Rosa roxiburghii show a lot of R. roxi traits in them.

So, the question is – how and what do I properly label my seedling parentage as?

2

Considering how readily apomictic seedlings occur when using difficult/unusual species as pollen parents, I wouldn’t be surprised to discover that is what plants like ‘Floradora’ really are. The pollen of R. roxburghii may have been used to make the cross but that doesn’t necessarily mean the resulting seedlings actually made use of the genetic material from roxburghii.

Thats one possibility, at least.

Jadae, you should bring some pollen down here to my greenhouses in April and May to hang some crosses! You get several weeks head start and no worries about rained out blooms. :wink:

Paul

3

Check out these two remontant first generation species hybrids both using the same species cross as pollen parent.

They look surprisingly alike despite having seed parents which are quite different.

Then there is this remontant species hybrid made from the same pollen parent that looks quite different

Link: www.helpmefind.com/rose/l.php?l=2.42471.0&tab=1

4

There are many possibilities that are difficult to sort.

Fact is that with many modern x species cross you get seedlings from allmost species like to allmost modern and quite recurent. So modern one wonder if any species contributed but nevertheless different enough for questioning.

And more so with species hybrids as Robert’s ones.

It is something I found among progenies I raised from i.e. Jersey Beauty as well as many other wichuraiana? x tea diploid older vars.

Concerning Floradora/Cinnabar why not consider the possibility of a modern 3n ovule meeting 1n roxburghii pollen. As has been found modern roses pollen ploidy may be quite diverse. The resulting seedling could be tetraploid and very modern looking as well as breeding.

I cannot explain Queen Elizabeth being so outstanding without some new species contribution.

5

I have been confused by Floradora and Cinnabar for awhile. I like that fact they are related to R. roxburghii because this got some very special black spot resistance compared to other roses. But these two roses show no real affinity to R. roxburghii. So are we to believe the parentage???

There are only a few possibilities I could think of. The simplest solution is the parentage is wrong but who would know what it would be without genetic mapping.

Second most likely possability that comes to mind is the possibility that the R. roxburghii that was used was tetraploid. but this would mean we now far less about roses then we think we do. For the only way I can see this working is if there is some growth regulation gene in their make up like dogs and apes have. These handful of genes change the whole organism by changing the developmental timing in the organism. But this does not seem likely because most species have a heavy influence on modern roses when the two are crossed together and yo would expect the same in these crosses if this was the case. The only real developmental genes I see are those for climbing habit and miniature ism one coming from what we typically think as miniatures, the other coming from polyanthus and the third coming from certain dwarf old european roses but while they have heavy influence both parent characteristics show through.

The third possibility is that R. roxiburghii has traits that split unevenly based on sex. I don’t know about this one I would have to look at more crosses and do some more of my own. But it is a possibility. You see at least some hints to this possibility in the Caninae sections and rugosa crosses with other types seem to favor either the female or pollen parent.

Assuming that R. roxburghii is a diploid then Baby Chateau would have to have a irregularity in sex cell division. When a parent show that it has irregularity in sex cell division it tends to keep this irregularity up. The good thing is that we have two roses that would seem to come from this cinniabar and floridora, the bad news is I can find no other yet to support this hypothesis. Secondly both cinniabar and floridora would seem more likely to have this irregularity. It seems to me when the irregularity is on the female side like that of the Caninae section it tends to carry over for a few generation but both of these rose tend to have regular sex cell division.

Another thought I have considered is gene incompatibility. May be it got the genes from R. roxburghii and did not know what to do with them. But I would expect some of these to come up in other generations. But more likely it would cause the plant to die early or fail to sprout in the first place. It is unlikely to have such a conflict lead to a sexually mature plant and even less likely to lead to two.

On much evaluation I am almost completely convinced that Cinnabar and Floridora are most likely self pollinated Baby Chateau seed and Tantau only thought it was R. roxburghii. So far I think most of these two roses traits can be explained by this. But I would still like genetic test to prove this before anybody changes the parentage.Does anyone know whether Floradora and Cinnabar was from the same hip. I doubt Tantau with all his experience could have made that same mistake twice on the same type of cross on two different occasions, but I can see it happening once.

Those are my thoughts I could be wrong. On your cross Jadae I would list both parents. But I would also put a note beside it that says you may doubt the cross and leave the note until some Rosa primula trait show through and prove you wrong.

6

Just a small historical note. I believe Tantau was questioned about these two crosses many times and stuck to his guns. In a book on roses (am not sure if it was Harkness’s or not) a group of rose growers were out in the field looking at the new upcoming crop and Floradora stood out among all the rest for its vigor, etc. The other growers knew there was going to be a future winner here, and for the next decade or so after it was introduced, Floradora was a parent in many of the crosses of that era.



This mystery has always intrigued me too; I guess we shall have to wait for DNA studies on this one to determine the definitive answer.

Jim

7

I hope someone takes on the project. As a side project in my Ph.D. as I was optimizing and learning how to run AFLP markers with lilies I ran some rose samples. Daydream seems much more like its female parent Lavender Dream than its reported male parent Henry Kelsey. The markers revealed that there is no evidence that Henry Kelsey contributed anything and that it is most likely a 2n egg witha little recombination between the homologous chromosomes leading to Daydream. Daydream is likely an apomictic seedling of Lavender Dream via diplosory. The chromosomes that had a little crossing over led to just a small bit of added homozygosity as some chromosome ends past the cross over likely became homozygous for a particular series of genes as it was duplicated and that section and the other section of that sequence in Lavender Dream lost.

I think comparing Max Graf to R. x kordesii may likely result in learning that R. x kordesii is not a self of MG, but a hybrid with something else due to the double flowers. There are lots of questions we can try to answer. Even though we pollinate with a particular male, like mentioned, does not mean its DNA is represented in the offspring or that only portions of what is in the pollen grain ultimately get through.

David

8

Isn’t it true also David that one would expect less genetic material to be transferred when using a diploid pollen parent with a tetraploid seed parent?

Wouldn’t we expect the resulting seedling to only carry a third of the genetic material from the pollen parent?

Also, might not there be caninae meiosis to consider when evaluating my seedlings out of glauca x pendulina pollen?

Thanks for any insight. Robert

9

Here’s what I wrote about Tantau’s roxburghii hybrids a while back:

http://www.rosehybridizers.org/forum/message.php?topid=6402#6404

I tried crossing R. roxburghii normalis with a number of diploids a few years ago. The only cross that took was R. rugosa rubra X R. roxburghii normalis. Unfortunately, I lost all of my seeds that year to a fungus. Maybe I’ll try it again this year.

10

That sounds fine, Paul.

I think I need to think about this topic more. It has too many plausible possibilities.

11

Hi David

Is not Daydream supposed to be from Henry Kelsey mother?

HMF says: Henry Kelsey

12

Hi,

I found some hybrid roses at a scientist

13

Roxburghii (the double and single forms) do have peeling bark, but mine peel not only on the years’ old wood, but often on the narrow new stems, way before they’d be called canes. The peeling is more organized than in the photo above: more like mature crepe myrtle woody stems. The flaky-ness above does suggest roxburghii

There is one other rose that I’ve seen peeling bark on: Lady Banksia. LB trunks are different in that they look normal until they are several inches in diameter, and then all heck breaks loose: longitudinal slits happen and a russet underbark that shreds and resembles a crinkled crepe paper emerges.

14

Hi Pierre,

Hmm. In Modern Roses it has Lavender Dream as the female. That’s interesting HMF has them reversed.

15

My roxiburghii normalis is a beautiful landscape plant in it’s own right. The bark is as ann describes but the stems are also reddish. What is nice about it is that there are few thorns, if any, so I can brush right through them stems and foliage without having to worry that I will scratch my faces or eyes with thorns while I am working outside :slight_smile:

16

In the past I had a hybrid of ‘Therese Bugnet’ x R. roxiburghii I planted at my parents. It unfortunately was a relatively small plant and never flowered. I have an op seedling of R. roxiburghii now that is vigorous and 7’ or so tall and appears to be a cross with some other nearby species (it was at the MN Landscape Arboretum and surrounded by other species). It is healthy and large and has more thorns that its mother, but unfortunately, it never blooms either. It is hardy, but just doesn’t every bloom. I had that one for probably 5 years now. It would be fun to try to use it as a parent.

Sincerely,

David

17

Curious. Would these be released into commerce under the dubious title of “neverblooming roses”? Who knows…perhaps its a niche waiting to be born!

18

Paul,

… Scary!

They maybe released as “neverseen blooming roses” because of an unusual habit of not blooming when people look at it.

19

David, I just ran across your mention of your

20

Hi Roger,

I suspect there are multiple reasons why we occasionally see “neverblooming” individuals among our seedlings. I firmly believe that genetic mishaps are high on the list of forces. Ralph Moore often showed me seedlings from extremely mixed (mongrel) crosses that he had grown for years in the hopes that they would eventually start to bloom, and even after a decade still had not shown a single flower. Clearly this wasn’t because of cold damage in his climate (although its always possible that these seedlings needed cold to bloom)

I too have occasionally encountered a seedling that didn’t bloom even after 5 years. I can’t comment on what might have happened after the five year point because none of these ever merited saving past that age. My climate offers a balance of cold but mild Winters that don’t generally result in freeze damage, so I am disinclined to think climate plays much (or any) role in this situation. Some seedlings are simply programmed to never bloom, I am sure of it.

Paul