Adair,
The disease resistance can be lost in the first generation, or it can be preserved depending on the other parent used. Either way, you will always have a mix of both.
Paul
It is obvious that the more the species is diluted the less it may alter desease succeptibility. Probably that is why my experience differs from Paul’s and others.
At the same time Moore did raise his hybrids and later I got a few thousand hybrids with species bracteata as the mother.
Allmost all progenies I got directly from bracteata are PM free.
There are degrees in spot resistance to reduced succeptibility.
The usual BS syndrome with defoliation all leaves falling with large spots and plant debilitation I see rarely if ever. There are smaller spots and slower deteriorating older leaves. New foliage remaining unaffected.
Many to most hybrids that do spot hold foliage longer and/or are strong nevertheless showing some tolerance to said spot deseases. If dilution occur this tolerance is quite transmissible.
Be it from BS partial resistance or succeptibility to other spot deseases I do not know.
It is obvious that the more the species is diluted the less it may alter desease succeptibility.
This applies to all traits, not just disease resistance. Breeders in the 19th and early 20th centuries knew this well. You can see evidence for this in many of the ‘most used parents’ posted by Dr. Kuska:
http://www.rosehybridizers.org/forum/message.php?topid=1754#1754
http://www.rosehybridizers.org/forum/message.php?topid=1753#1753
Happiness, the old work horse of Herb Swim, is a good example. It has five successive generations of both chinensis and moschata, thus fixing both scent and repeat blooming. Later on there are two successive generations of foetida that fixed hard yellow, and I would guess even more included among the unknown parents.
Pernet-Ducher’s Antoine Revoire has a double dose of Champneys’ Pink Cluster in one close generation and a quadruple dose in the next. It’s a shame his father didn’t keep records but there’s no doubt he used foetida over and over as well.
It’s not so much that any one breeder deliberatly set out to do so, but rather that the roses that had these backgrounds are the ones that wound up in their repetoire.
We can see this even today with our own most favored parent roses. Joycie has been much discussed of late. Well, the roses that Ralph Moore chose to work with that led to Joycie have among them no less than nine successive generations with direct injections of foetida, and most of these generations have double or even triple doses. Moreover, in the nine generations before that there are many tens of doses of both chinensis and moschata in each and every generation.
So for capturing Bracteata’s strengths then, it might make sense to not limit oneself to Ralph Moore’s hybrids but rather to go closer to those with more of it in them, and use them copiously.
Seafoam is another good example. It is used a lot due to it’s almost unique (The Fairy has it too) plant habit of wanting to hug the ground. That rose is self x self x self lol. And then used a bajillion times by Meilland in their roses.
I’ve read some very mixed reviews of R. Bracteata itself - apparently it suckers a lot, and can be hard to manage. I still have a whole lot of room in my garden, even after planting 38 roses this season (especially if I end up tearing out some random plants I don’t really want anyway). If I want to really get into trying to hybridize bracteatas, do you think I should get myself a R. Bracteata to try to work with?
Thanks a bunch!
(PS - I hate to be obnoxious with all my questions, but this year is my first working with roses, and I’m absolutely fascinated by it, and I am just so impressed with all you’ve managed to accomplish!)
Adair,
there is nothing obnoxious about asking a lot of questions; thats what we formed this forum for!
I second Don’s comment: don’t limit yourself to the Moore Bracteatas in breeding, but include other strains as well. While Ralph’s work has been very meaningful and valuable, his are not the only sources of good Bracteata genes. However, I would definitely include ‘Out of Yesteryear’ in your work, as it has gotten past the fertility barrier and passes on some very good qualities to its offspring. The fertility barrier is actually fairly difficult to get around in working with R. bracteata, species.
Paul,
Do you have any suggestions for getting around the fertility barrier? I saw on another thread someone said TNT was not a good option - not that I even would have considered it!
Also, do you know the source of the fertility barrier - is it something to do with the differences between diploid/triploid/tetraploid, or something to do with the nature of the pollen or seeds (I know some species of pine require fire for the cones to open to allow germination, for example), or something else entirely?
I have 3 Out of Yesteryears I just planted maybe 2 weeks ago. I read your comments on here about the parenting abilities of Incantation, which I got from Rogue Valley about a month ago - do you think it would be possible to cross those?
Thanks so much, I really appreciate all the advice and explanations.
Fertility problems arise for a number of reasons, including, but not limited to, ploidy. In the case of R. bracteata I think it has more to do with how dissimilar the two parent plants are. In other words, if the parent you use on R. bracteata is from a very different group, you can anticipate some fertility problems. Its all luck of the draw. Experiment and see what happens.
If I were starting from scratch with R. bracteata, I wouldn’t use HT’s or most modern HT derivatives, but would instead find some Diploid Poly’s or Hybrid Musks to cross with: something that blooms a LOT in panicles, rather than one to a stem. ‘Blush Noisette’ would be a great place to start, for example. That rose is bulletproof in my climate. It might also be worthwhile to go back to the early Chinas for breeding it as well, like ‘Old Blush’ and maybe ‘Slater’s Crimson’.
Regards,
Paul
if the parent you use on R. bracteata is from a very different group, you can anticipate some fertility problems…fertility barrier is actually fairly difficult to get around in working with R. bracteata
Based on my own extrapolation of Byrne’s phenetic tree to Koopman’s phylogenetic tree you might try roses also heavy in laevigata, clinophylla and/or foetida, which seem to actually be the next closes species to bracteata. But the Chinas are close too.
Seafoam …‘Blush Noisette’…‘Old Blush’…‘Slater’s Crimson’.
Also, Pearl Drift because of it’s heritage. I have read the accounts here of its propensity to mildew, etc, but it is fertile and, with 25% bracteata and balance heavy in Chinas, a prime candidate for continued injections of bracteata to weed that out.
Prima would probably be better than Pearl Drift.
btw, Im not exactly fond of rosa bracteata, but a larger-flowered type may sway me. The species/mini mixes never did anything for me. Maybe one could less the thorns in a large hybrid?
Also, I wouldnt mix it with Sea Foam. That sounds incredibly painful.
How hardy is R. bracteata? I ordered it from Loubert in France, but I am zone 7, sometimes leaning to 8, especially last two years with very mild winters (some frost, some freezing days but never enough for real ice skating, some freeze thaw cycles). HMF says zone 7a. Will it be OK? Will it survive suddens very cold drops at night?
Paul, why do you stress heavily cluster flowered roses? Is that because they are close to R. bracteata or because R. bracteata does no bloom in clusters and this would increase bloom production?
Rob
Jadae said,
“Maybe one could less the thorns in a large hybrid?”
Yes, I’m working on it.
I have several new seedlings coming along, but only one smooth one so far, a yellow mini from work I did two years ago.
It is pollen fertile so I’m spreading it around. A full size seedling will pop out of the mix. It’s bound to happen.
Rob,
It was just one suggestion to increase the amount of bloom you might get. I think larger panicles are a good thing, in all roses.
Paul
Yea, R. bracteata is kinda sparse in bloom here. However, it is fully hardy in our zone 8b
btw, I may try Baby Faurax x Rosa bracteata.
So if one wanted to create a yellow, hypothetically, what would you recommend to cross?
Alexander Hill Gray? Lady Mary Corry? Safrano?
I didn’t realize the fertility problems existed. Out of Yesteryear should have a lot of yellow potential in it, but isn’t it a triploid?
Does Clinophylla have similar fertility issues?
Out of Yesteryear is indeed a Triploid, but there are many Triploids that are highly fertile. See the article David and I wrote on the subject, URL below.
This abstract is for a paper that specifically addresses the issue of fertility and ploidy level in roses and basically confirms what David and Paul wrote:
"Acta Bot. Gallica 149 (4) : 405-413 (2002)
"Chromosomes studies of rose cultivars : application into selection process
"Par C
Don you do not give your e-mail link. This may be out of date, but Grossi’s fax used to be (334) 04 72 43 14 26.
Hi Henry,
Thanks, I was hoping to send an email but a fax will do. My email is don ~at~ holeman ~dot~ org. I was putting it in the box for a while when I posted but the email function doesn’t seem to be working so I stopped. I wonder if there’s a secret to it.
Do you know Dr. Grossi? There are three papers I want to read of his, I don’t suppose you have them?
- “Rosa Taxonomy and Hierarchy of Markers Defined by ACT STATIS” which appeared in the journal Z. Naturforsch., 54c, 25