All A'Twitter x Yatkan

A meeting place for rose breeders.
mntlover
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Re: All A'Twitter x Yatkan

Post: # 70540Post mntlover
Thu Oct 31, 2019 4:34 pm

Joe, thank you for the detailed information. I am looking for at least snow level cane hardiness in zone 5 and eventually zone 4, but that is at the point of attaining good repeat bloom along with beauty and fragrance. A lot will depend (I think) on generations required to reach good repeat bloom and how well cold hardiness can be maintained through those generations. Certainly snowline hardy in zone 3 seems like a great starting point for me in my goals, provided I can work for several generations without becoming much more tender.
Any thoughts on various avenues that could be used to try and accomplish that if it takes a couple more generations to gain the repeat?

By the way, I love that fragrance (thinking Gertude Jeckyl for example, along with many old roses), although I also love Tea rose and a myriad of combinations of scents.
thanks again!

Oh yes, I gathered seed from what I believe to be Rosa woodsi this fall when camping. I also got seed from a rose I found camping up in the North Cascades that was at pretty good elevation, not sure what it was, but figured it might be pretty hardy. Anyone experience with germinating seed from Rosa Woodsi?
Duane

jbergeson
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Re: All A'Twitter x Yatkan

Post: # 70548Post jbergeson
Thu Oct 31, 2019 10:29 pm

It is likely that your R. woodsii seed could benefit from a warm stratification period prior to the cold stratification.

If you're in zone 5 that should make your work easier, because the once-blooming seedlings in the first generation of a species-modern cross should be able to have enough live wood to bloom. Then you cross the best of them with another rebloomer and select for juvenile bloom in that F2 generation. In theory, about one in six of the (modern x species) x modern seedlings should bloom (assuming tetraploids). If working with a diploid species, it should be easier to recover rebloom but also the species' influence will be diluted more quickly.

To be realistic... modern x species cross made in 2020, F1's germinate spring 2021, F1's bloom in 2023 and the best are crossed with moderns immediately (in both directions to maximize chances of success). F2's germinate in 2024. About 1 in 6 of them bloom that spring (juvenile bloom is a reliable predictor of remontancy) and are your first reblooming seedlings with 25% species blood. Maybe your F1's could bloom in 2022 if you have a longer growing season.

Plazbo
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Re: All A'Twitter x Yatkan

Post: # 70550Post Plazbo
Fri Nov 01, 2019 3:24 am

jbergeson wrote:
Thu Oct 31, 2019 10:29 pm
If you're in zone 5 that should make your work easier, because the once-blooming seedlings in the first generation of a species-modern cross should be able to have enough live wood to bloom. Then you cross the best of them with another rebloomer and select for juvenile bloom in that F2 generation. In theory, about one in six of the (modern x species) x modern seedlings should bloom (assuming tetraploids). If working with a diploid species, it should be easier to recover rebloom but also the species' influence will be diluted more quickly.
The other option is sib/selfing the F1 for a 1 in 36 juvenile bloom in the F2 (compared to 1 in 6)

Sure the odds are low, you'll get only approx 27 out of 1000 so would need to harvest a lot of seed but you'd be able to cull very quickly for juvenile bloom so space shouldnt be a huge issue and you'd retain more of the species which is possibly a better breeder/bridge for whatever you're hoping to get from the species.
Anyone able to send rosa californica (op) seeds to me in Australia?

jbergeson
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Re: All A'Twitter x Yatkan

Post: # 70553Post jbergeson
Fri Nov 01, 2019 1:59 pm

Good point, Plaz.

I'm trying some outdoor seed plots this year to plant larger quantities of OP seed from the aforementioned modern-species F1's, planning to scout for those 27 out of 1000.

Plazbo
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Re: All A'Twitter x Yatkan

Post: # 70554Post Plazbo
Sat Nov 02, 2019 1:49 am

It's something that I'm doing myself. Even though the eventual plan is to be mostly diploid there's a lot of traits from higher ploidies that I'm hoping to move down to diploid which are often attached to once bloomers or older classes without juvenile bloom. Making triploids that are once blooming (and potentially sterile without being able to determine for years) is a space commitment that I don't have the luxury of. So need to maintain the traits I'm looking for and acquire juvenile blooming, maintaining the traits for the most part requires not moving too far away from the source too quickly as the genes involved seem to generally be quantitative in behaviour....so a lot of sib/selfing F1 is stacking those two goals for the tiny fraction of juvenile bloom and potentially more of the once bloomers other traits than if crossing with a second modern.

The more fun one I'm working on and has unknown (but likely far worse) odds is Rubiginosa x Modern (thornless, because why not). Based on the results of someone with Canina X Spinosissima and the F1 being the expected mostly canina like in appearance but the F2 being an array of ploidies as the meiosis broke down. In theory juvenile (tetra or dip) rebloomer could be possible in the F2 without diluting the foliage scent genes too much, just may take something crazy like a million seedlings to find (hurray for 25+ seeds a hip...)....impossible odds here I come. Have already seen some odd results from Lord Penzance selfs that look mostly spin (and have the spin die back, dead wood grossness) rather than rubiginosa so that's encouraging (to me).
Anyone able to send rosa californica (op) seeds to me in Australia?

Karl K
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Re: All A'Twitter x Yatkan

Post: # 70794Post Karl K
Sat Dec 28, 2019 2:00 pm

Plazbo wrote:
Wed Oct 30, 2019 5:50 pm
In warmer climates (india, pakistan) centifolia reportedly sets hips, the cause of that Im not sure of. Its likely fuss in what pollen it accepts and heat stresses can alter how blooms develop ...
I remembered a comment that seems to be appropriate here.
Rowley (1960) wrote about triploid roses.
Hip set is undoubtedly affected by environment, especially the weather at the time of anthesis. Ideal conditions may stimulate a "sterile" individual to mature seeds. Thus although Cardinal de Richelieu has never set a hip outdoors in the eight years under observation at Bayfordbury, Sam McGredy tells me it will do so occasionally under glass.
http://bulbnrose.x10.mx/Roses/breeding/ ... loids.html

Wulff (1959) also tackled this subject, and reported an odd example.
The ancestry of Schneeschirm, an ornamental rose, is not quite clear. It blooms twice a year. The first flowering period lasts from June to August. The second begins after a short interval, and ends with the first frosts.

It is a very remarkable fact that the flowers of both periods differ in their meiotic behavior; only those produced during the first period are able to produce hips and viable achenes. Their reduction division is characterized by the occurrence of only 0-3 trivalents, with pairing to 7 bivalents and 7 univalents or 1 trivalent, 6 bivalents and 6 univalents. This reduction division proceeds rather regularly. The univalents, splitting twice, are mostly taken up into the young tetrad nuclei. Chromosome elimination is low, and so viable pollen grains and egg cells will contain 14 chromosomes.

The offspring of about 60 plants were tetraploid, each seedling having 28 chromosomes in the root tips.
http://bulbnrose.x10.mx/Roses/breeding/ ... ploid.html

And a bit further afield, I have another curiosity involving wheat. Lyubimova (1960) discussed environmentally induced variations in pollen viability and content. Fig. 5 is particularly instructive. She wrote,
We are justified in drawing a definite conclusion from the results obtained. In many hybrid forms the processes of micro- and macrosporogenesis are subject to considerable variations, depending on the conditions of the environment in which they take place. Changes of environmental conditions lead principally to modifications in pollen sterility of the hybrids. Under the same conditions no modifications in meiosis and fertility are observed in old species.
http://bulbnrose.x10.mx/Heredity/Lyubim ... _1960.html

It is not difficult to imagine a variety of hypotheses to explain sterility in an excessively double flower, but why would this sterility extend to semi-double and single flowered sports. Then again, I have a report involving petunias. The original double-flowered form was seed sterile and had to be reproduced by pollinating a normal form of the species. Myrtle Francis (1915) worked the strain and produced a beautiful and odd bunch of varieties. She got the seed-fertile doubles that she wanted, along with a single-flowered specimen that was completely sterile. I don't have a clue how that last one came about.
http://bulbnrose.x10.mx/Heredity/Franci ... unias.html

Plazbo
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Re: All A'Twitter x Yatkan

Post: # 70795Post Plazbo
Sat Dec 28, 2019 7:19 pm

I don't know if it's the heat wave or the excessive amounts of pollen (ie 2 or 3 times a day for 5 days...seemed easier than looking for pollen that may or may not be found) but I have hip set on Crested Moss that I got this year. A lot of them seem to be phantom pregrancies (ie I can't imagine seed being in the hips with how small they are) but others have hips as big of Gallica hips that I can't imagine not having seed in them. Will find out in the next few weeks though when they are ready to harvest.

Helga Brauer is another rose from Crested Moss as seed parent (and took the breeder something like 20 years of attempts...but he's in a slightly cooler zone) so Crested Moss is clearly not as sterile as thought but also not particularly willing either.

On a side note, also had hip set on Robusta this year (never previously). Stanwell Perpetual still refuses (and branches frequently die) it clearly has some issue with the environment.
Anyone able to send rosa californica (op) seeds to me in Australia?

Karl K
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Re: All A'Twitter x Yatkan

Post: # 70798Post Karl K
Mon Dec 30, 2019 3:50 pm

Plazbo wrote:
Sat Dec 28, 2019 7:19 pm
I don't know if it's the heat wave or the excessive amounts of pollen (ie 2 or 3 times a day for 5 days...seemed easier than looking for pollen that may or may not be found) but I have hip set on Crested Moss that I got this year. A lot of them seem to be phantom pregrancies (ie I can't imagine seed being in the hips with how small they are) but others have hips as big of Gallica hips that I can't imagine not having seed in them. Will find out in the next few weeks though when they are ready to harvest.

Helga Brauer is another rose from Crested Moss as seed parent (and took the breeder something like 20 years of attempts...but he's in a slightly cooler zone) so Crested Moss is clearly not as sterile as thought but also not particularly willing either.
Ralph Moore made use of 'Crested Moss', but as pollen parent.
http://bulbnrose.x10.mx/Roses/breeding/ ... OSSP2.html

I don't recall ever seeing a hip on 'Stanwell Perpetual' growing in Palo Alto. I thought I'd read about its low pollen viability, but couldn't find anything in my notes. That is one plant that might serve as barbed wire, if one had a need.

If I had lots of time and room, and a more suitable climate, I'd like to cross 'Doorenbos Selection' with the Portland Rose to raise a red-flowered companion for Stanwell. Or substitute "Portland from Glendora" for a more doubled version.

I'm glad I keep notes:
From: "ivanlouette2002" <ivan.roses@wanadoo.be>  
Date: Sun, February 22, 2004 4:07 am  
To: ChezVibert@yahoogroups.com  

Roses sterility isn't easy to prove !

Because sterility was discussed about FDY I want tell you two little histories from my rose garden.

The most interesting observation I did about that was with the Pimpinellifolia hybrid 'Stanwell Perpetual' (one of my preferred). For a long time after planting it in my rose garden it didn't produce any hips, but after planting close to it a wild semi-dwarf pimpinellifolia form from the "Péninsule de Quiberon", it has produced each year a lot of hips, however each one with only one to three achenes in it. These achenes are fertile and gave me some wonderfully perfumed varieties, as 'Paula Vapelle' which has a lot in common with the small wild pimpinellifolia above (its perfume is the same but strongly increased by the influence of 'Stanwell' ; at first time in cold days, it is close to Convallaria majalis, and when the sunny and warmer days come it moves to orange smell). 'Paula Vapelle'is also much more fertile than 'Stanwell Perpetual', and like most other ones in those 'Stanwell''s seedlings, after a big splash in May-June it produces flowers up to the first autumn frosts. In this case, the intervention of a botanical species already involved into the parentage of the variety was perhaps helpful.

On the other hand, my friend the late Louis Lens gave me a very strange plant he called "Bizarre". This plant is a seedling from one of his pots but with an unknown origin. The stems have a sculptural irregularly curved growth and the leaves are leathery, irregular and strong like those of some appletrees. The most special is that it produces bark up to the the pedicels and the flowers receptacles and up to the rhachis of the leaves. Its hips don't develop perhaps only because of a physiological problem, but its pollen has proved to be fertile (one friend tried it) and two natural seedling found in its area have inherited of the "bark" character (probably an hybrid with my variety 'Ma Basanée' and another one with 'Prosternation') In this case, the varieties which produced the seedlings were of the Synstylae section.

Like some appletrees, it seems that some roses varieties need a particular pollinator.

ivan

Plazbo
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Re: All A'Twitter x Yatkan

Post: # 70799Post Plazbo
Mon Dec 30, 2019 7:35 pm

I just mentioned Stanwell because I recalled that post above from Ivan to some extent (that he got hips and seedlings from it). I figured given it's one of the commonly "sterile"/doesn't set hips in similar manner to Crested Moss and Robusta (which have set hips for me this season) that it's trigger is probably not heat related.

What I didn't recall was that he had it next to a wild selection of the species something I may be able to test next year should my own root spinosissima decide to grow (it got to about a foot and decided to not do anything above the surface since, possible semi dormancy due to heat...stanwell also seems to dislike the heat, it's canes often die back and new ones appear when it's cooler).

I wish Doorenbos Selection was here, but like many things it's not. It may be useful in one of my goals, purple flowers with black hips...step by step, will get there eventually.
Anyone able to send rosa californica (op) seeds to me in Australia?

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