I have 5 hybrid (acicularis/Nutkana/Calocarpa) acicularis plants that I have used with crosses and have not differentiated the resultant hips/seeds/offspring to any one parent. However I have also obtained several offspring that have been reblooming, one of which is fertile and has produced nice 2nd generation reblooming offspring. Is the quickest way of determining which of these 5 hybrids is producing dominance (one obviously is)for rebloom, by crossing each of the 5 with a modern in large enough numbers and hopefully one of them produces a couple of rebloom dominant offspring (that bloom and are tagged with (ABCDE) some sort of identifying tagging)? From the last two yrs it looks like I am getting about one out of ten (some get discarded or die before reaching immature bloom-so these numbers are not accurate to use) of the survivors that rebloom. I have gotten rebloom with Cafe Ole, ELLE, Prairie Peace, and Lady of the Mist (not sure of the last one) x Hyb. acicularis, with the acicularis as the mother in most of those crosses. Are there any other options that do not require so many seedlings? One of the 5 Hybrid acicularis has produced several scattered reblooms the last two yrs. which I at first attributed to the extreme heat/drought forcing a semi dormancy but now I am not so sure. Maybe that is my rebloom dominant mother?
So far I love the vigor and dark green foliage of the five seedlings you gave me. None has bloomed. I sure hope I get similar results and land some rebloom when I start to work with these! I also have a number of my own seedlings of this cross from seed that you sent me. They are very small. This is the first winter for all of them, so we will see about hardiness here in zone 3.
Iâm surprised that youâve gotten rebloom from Prairie Peace. I have not. I did just dig up a pretty healthy seedling that was obviously from PP and looked at the tag and it was Double Knock Out x Prairie Peace. Thatâs pretty cool. I will store it inside and pot it up in the spring to see if I can get some blossoms.
Iâve had the same thought. What if you have a F1 cross of a modern reblooming tetraploid with a once-blooming tetraploid species rose, then you self-pollinate them to create an F2 generation. A very small number of the F2âs may rebloom, but the vast majority will not. However, among them there would be some with three reblooming alleles and only one dominant non-reblooming allele. (not sure if I have the right term, using âalleleâ.) Those plants would could be used to cross with reblooming moderns to give a fairly high number of rebloomers, but there would also be some plants that would give almost no rebloomers. Especially in my situation it would be so nice to know which plants could pass on rebloom, because I have to dig them up and store them inside to even see a blossom. Anyways, itâs not possible and I am just babbling.
Are there any other options that do not require so many seedlings?
Comparative morphology.
This is one where Donâs DNA magic wand would work. Because we know exactly what mutation makes roses rebloom, it would be possible to screen DNA from each of those mother plants with a PCR reaction. The mutation is a transposable element inserted into a particular gene. so the PCR product would be very long for the alleles that were mutant, and short for those that werenât. With luck you might get an estimate of copy number 0,1,2,3 of the long form. That would take a little more work as it would probably be done by âreal-timeâ PCR.
An alternative would be to find restriction enzymes that cut in the right places and then run gel electrophoresis followed by a Southern blot. Thatâs kind of out of fashion these days but it works when PCR fails (fairly common with plant material.)
I donât recall but I expect that the groups studying the rebloom character probably have done the PCR thing already. If I were running a big commercial operation I would do it for sure.
Unfortunately I donât know of any methods that are not hi-tech.
There you go again throwing those big words at us. Looked them up and it meant what I thought it might mean. Not going to happen on my watch-I was an art major, not a botanist, biologist or a chemist. I think I can rule out one of the plants because I do not remember ever doing any crosses with it, but that still leaves quite a few seedlings with the four others. But I will tag them with specifics and try doing just that I guess. Since these all came from Henry Kuskaâs OP (Calocarpa X Nutkana) X Acicularis OP there might even be a chance that more than one is pairing up with the recessive rebloom genome. Just wanted to know if there was a real âmagic wandâ not just a high tech one.
I donât mean to get tangled in semantics, but you may be observing weakened dominance of once-blooming, rather than increased dominance of reblooming.
We are told (repeatedly) that the once-bloom trait is dominant over everbloom. But now and again we see some degree of repeat bloom in hybrids that should be strictly once-blooming. In my many visits to the Heritage Rose Garden in San Jose, I could usually find a bloom or three on âPaul Noelâ and âFrançois Juranvilleâ, two of Barbierâs Rosa luciae hybrids. Another of this group, âFrançois Foucardâ, was even more reliable.
Then there is âMme Norbert Levavasseurâ (Crimson Rambler x Gloire des Polyantha). This variety reblooms consistently, though sometimes the once-blooming trait shows itself, slightly, with longer canes than would be seen in a ânormalâ dwarf Polyantha. Furthermore, Dr. Van Fleet observed some oddness when breeding from âMme Norbertâ:
Journal of Horticulture and Home Farmer (May 23, 1907)
Breeding from the Baby Rambler Rose.
A number of cross-bred seedlings, grown from Baby Rambler [Mme Norbert Levavasseur], are disappointing in that none turns out to be constant-blooming, though largely pollenised with ever-blooming kinds, says Dr. Van Fleet in âRural New Yorker.â All came near to the Crimson Rambler type, regardless of the habit of the pollen parent, and will probably develop into tall-climbing annual bloomers. When pollen of Baby Rambler, which has the continuous flowering Gloire des Polyanthes as one parent, is used on the stigmas of annual-blooming Ramblers of Wichuraiana hybrids, very dwarf ever-blooming plants result in large proportion, and something may perhaps be done to develop a useful group, of which Baby Rambler will likely remain the type.
This variation in dominance can be altered by selection: sexual or vegetative. Nicolas (1937) discussed how Reymond transformed âGeneral Jacqueminotâ into a freely reblooming variety by vegetative selection.
http://bulbnrose.x10.mx/Roses/breeding/Nicolas_Reymond1937.html
Similarly, Moreau-Robert (1882) persuaded his once-blooming âCommandant Beaurepaireâ to rebloom.
http://bulbnrose.x10.mx/Roses/Rose_Pictures/C/CommandantBeaurepaire.html
Here is some further information on dominance modification:
http://bulbnrose.x10.mx/Heredity/King/DominanceModification.html
Furthermore, some of the hybrids derived from once-blooming and everblooming parents turn out to be everblooming, but only during the winter when raised in mild climates and under glass.
Everblooming Roses for the Out-door Garden of the Amateur pp. 39-54 (1912)
EVERBLOOMING HYBRID REMONTANT ROSES
Georgia Torrey Drennan
âCharitably granted the weakness of blooming but once a year, paradoxical yet true, both General Jacqueminot and American Beauty must be accorded high place among everbloomers. They simply reverse the season. Their bloom time is winter. Florists find them as constant during the winter months as the Teas during the summer.â
I observed the same thing in âBelle Portugaiseâ as I enjoyed a fine old specimen in Belmont, CA, flowering intermittently from November through April or May.
And Masuino (1960) wrote:
I had more interesting results from the cross > R. chinensis minima > (Tom Thumb var.) x > R. banksiae lutescens > and its reciprocal. The series of hybrids obtained varies from the dwarf ones of about eight inches to the big climbing ones; some thornless, all having good ornamental foliage. The blooms are white, in corymb, long lasting and very decorative.
A climbing plant which seemed to have no everblooming habit has now improved giving a profusion of sweetly scented double flowers which, from December till July, form a candid cascade. During the August-November period the luxuriant glossy foliage compensate for the lack of flowers.
Finally, there is a very old rose that was the first âCommon Chinaâ. It also picked up an assortment of other names, such as âIndica Majorâ and âBengalensis Scandensâ. It was usually regarded as once-blooming; but according to AndrĂ© (1874):
Rosa indica major > is almost naturalised throughout the whole of this region [south of France]. It possesses the additional claim to favour of flowering nearly all the winter, forming beautiful hedges of dark green shining foliage, from which thousands of clusters of lovely flowers rise, of a tender delioate transparent pink, or almost pure white, with a brighter tinge in the centre and at the tips of the petals. This Rose is an evergreen, and makes an excellent stock for grafting or budding.
I remembered another example, âMlle. Cecile Brunnerâ. A friend emailed me back in 2004:
" I used to manage a nursery for an old Dane, for 7 years. We sold hundreds of CB each spring, these were all east Texas grown budded plants. Then by summer, customers would come in to complain that their spring planted CB roses were not all the same. Some were climbing and taking over the gardens. Some made large shrubs and others were normal. Taking this in stride, we expected the comments, it happened every year. In fact, we expected to hear the reports âŠit was a hidden chuckle behind closed doors! I do not think that there is any bud selection on cheap non patented roses that are mass produced. Price is the only consideration, âŠa cheap price."
He thought the stock was a chimera. I suggest that the results indicate fluctuating dominance.
Moore (1967) offered some further evicence:
In my own work several important and interesting seedlings or groups of seedlings have been observed over the years, which may throw further light on the subject of origins. First, many years ago, before I had ever heard of a miniature rose, a very small flowered plant appeared in a lot of seedlings grown from a plant of Climbing Cecil Brunner. The seed hips had self-set naturally and the plant was well away from other roses. A fairly large population was grown but most were once-blooming multiflora type plants with single or nearly single (five petal) flowers. Two or three resembled the parent and were everblooming; a few were low bushes. One plant of arching, climbing habit to about three feet had small foliage and tiny one-inch, double near-white flowers. Buds were tiny, about the size and shape of > R. rouletti. > Five or six plants were propagated but all were destroyed while I was away at college. Today this would be classed as a true miniature climber.
Miniature Roses