Since receiving the seed from China and then germinating them, I have wondered if there was an alternative way of breeding Hulthemia Hybrids from what has already been achieved.
I noticed that most hybrids were developed using a lot of multiflora hybrids as the pollinators. I then wondered about using fertile modern triploids which were developed here at home from China origins. Another possibility to obtain a cross and cold tolerance as well would be the use of :
R. eglanteria (rubiginosa) with its 4 + 1 setup
R. rubrifolia 3 + 1
R. pomifera (Duplex) 3 + 1
The use of the F1 (R.Virginiana X Sympathie) although a tetraploid, I feel because of its breeding, has a 3+1 setup and could possibily create another direction of breeding these lines. R. carolina hybrids could also be used in this way as I feel the setup would be similar, but also very different.
The use of caninae would take a little longer to achieve results, but with the health issues of current Hulthemia hybrids, I feel this may sort out the bugs and also create an interesting path for future hybrid crosses.
I do like the idea of crossing with caninae but I wonder if this would be counter productive for you to dilute the genes you want this much in the first generation. It would be interesting however.
I wonder how the spines on the hips would react to moss rose genes myself.
My bad I thought you were going the other way with these crosses. With the Canina as a seed parent. But this is a very nice way to go about it. Plus you will be more sure of crosses this way using these as pollen parents. The R. rubrifolia might cut down on the powdery mildew that is suppose to plague Hulthemias\rose hybrids early on.
With the thorns I was just wondering what the moss gene would do to it.
Adam according to Cocker and Harknessâs work, results are better if Hulthemia is used as a seed parent than a pollinator. All of the cultivars which I am going to use are very sound health wise and what the Moss gene would do, using my Laneii, it would be real nasty.
Warren, Iâm sure that most of us donât have access to the former-Hulthemia species to even attempt the sort of crosses youâre describing, but I hope you get some good input from the few souls that may have.
Do you really feel that the early crossing with âTrierâ (itself a rather healthy rose) resulted in poor health down the line? The breeders who have worked the most with hulthemia hybrids to date havenât lived in regions with the highest blackspot pressure, so they may have made choices to use non-hulthemia breeding parents in each successive generation that others might not. While there may be certain striking differences in the first generations between a hulthemia-Caninae hybrid and one involving a diploid heavy in Synstylae influence, I wonder if those differences would be significant enough after numerous generations of crossing to justify any difficulties that might arise from involving Caninae species at the earliest stages in the process. Also, I would not say that those Caninae species are especially good sources of blackspot resistance in particular, or at least they arenât for this (humid eastern US) climate. You could just as easily work by crossing modern, repeat-blooming hulthemia hybrids (once you have them or have created some of your own) with those species or others and recover repeat-bloom faster and with less dilution of quality traits; fertility in the first and second generations should also prove better.
I donât say that to discourage the attempt in any wayâI think that if you have the germplasm at your disposal, you ought to try crossing it with everything but the kitchen sink!
Do you really feel that the early crossing with âTrierâ (itself a rather healthy rose) resulted in poor health down the line?
In this paragraph I have wondered if there was an alternative way of breeding Hulthemia Hybrids from what has already been achieved.I noticed that most hybrids were developed using a lot of multiflora hybrids as the pollinators. it was not about poor health but the hint that most early Hulthemia Hybrids contained a limited gene pool which was Multiflora.
While there may be certain striking differences in the first generations between a hulthemia-Caninae hybrid and one involving a diploid heavy in Synstylae influence, I wonder if those differences would be significant enough after numerous generations of crossing to justify any difficulties that might arise from involving Caninae species at the earliest stages in the process
The answer to this is in the above sentences as well.
[iThe use of caninae would take a little longer to achieve results, but with the health issues of current Hulthemia hybrids, I feel this may sort out the bugs][/i]
If you look at Euphrates and even those Hulthemia Hybrids by people here on this forum , mildew is the problem. I am just trying to find an alternative solution .
Mildew came with Hulthemia. R.x Hardii was described as needing to be grown in a cold, airy green house as it is a martyr to mildew. Iâd think crossing the species with something like Maytime, which Walter Lammerts proclaimed âimmune to powdery mildewâ or Basyeâs Legacy, which also appears immune, might cure that ill. Nigel Hawthorne is the only one of the Harkness Hulthemias I grew which never mildewed.
If you go through the work of Harkness, all pollinators were of a diploid nature, I would say they would have tried some pollen of higher ploidy levels but may not have succeeded.
Here even if spraied and greenhouse grown Hulthemia is a poor plant.
If I were able to grow it I would cross with wichuraiana or Immensee hoping to get fertile diploid yellow spotted stronger plants. Sibcrossing the progenies to recuperate a population with Immensee reccurence and a lot better than Trier desease resistance plus Hulthemia flower color combo.
Somehow a breedable better Tigris population that would preserve more genetical diversity.
You said that âI have wondered if there was an alternative way of breeding Hulthemia Hybrids from what has already been achieved.I noticed that most hybrids were developed using a lot of multiflora hybrids as the pollinators. it was not about poor health but the hint that most early Hulthemia Hybrids contained a limited gene pool which was Multiflora.â
My contention is that the early use of Rosa multiflora-derived parents doesnât really limit the gene pool much at all, even in the earlier commercially available hulthemia hybrids. If you have a premium membership at HMF, start looking at some of them and click the âParentage Bloodlineâ option under the âLineageâ tab. âTigrisâ only has a 12.5% identifiable contribution by Rosa multiflora, and this is only diluted further with each successive crossing. If you look at âBullâs Eyeâ for a more recent example, youâll see that the genetic contribution is reduced to under 2%, while the contribution of the more recent parents is massive by comparison. Most of Jim Sproulâs new releases donât have their parentage included, but they arose from even more generations of crossing, with each one reducing by half again the contribution of genes from the most original parents. Ultimately, only the petal blotch gene or genes might remain from even the Rosa persica ancestor.
When it comes to that initial cross between Rosa persica and something else, then, high fertility with hopefully enough disease resistance to survive is the real goal, because that plant is just a vehicle for delivering those hulthemia eye blotch genes to a future generation where the real work of improvement happens. If, however, youâre interested in an F1 garden plant from a hulthemia cross or maybe something out of the second generation, then breeding it with something that will completely offset all of its bad tendencies makes more sense.
Heck, if I had the species, Iâd be working with the healthiest, most fertile minis I had at my disposal. Ralph showed how they can be used as bridges between the traits you seek to pass on and decent results, fairly quickly. Not perfect, but what is? Imagine the time saved by engineering in dwarf, repeat flowering at the foundation rather than many generations down the line. The only multiflora type I would use is the found rose, Pookah, which I know isnât readily available there, Warren. But, it is the only of its type which (here) doesnât experience chlorosis due to the alkalinity; never suffers any fungal diseases in my garden; propagates like the weed it is; remains within bounds instead of throwing rampant growth and flowers incessantly. The color is a good, saturated pink which holds quite well until the flowers are well spent. Based upon local performance, it SHOULD displace Ballerina completely.
I understand where using other, more cold hardy things would benefit those in more arctic climates, but Hulthemia would probably not be suitable for those types in the first place. Caninae is completely unsuitable here, though itâs been âdiscoveredâ further north as âfound rosesâ.
The problem with both multiflora and the canina family is their dominant lighter eye. However, Rosa canina itself has a superior saturation to multiflora.
Iâd be curious if R. soulieana would be superior.
If Souliena is superior, Ralphâs version of it would be the one to work with as it gives repeat in the first generation with the proper parents. However, it did bleach out Anytime in MORsoul (String of Pearls).
How much is early generation Hulthemias health due to the other parent and how much is it due to the fact that it is a really wide cross? Maybe you are getting resistant genes but the resulting plant does not know what to do with it. It is like trying to run a computer program from one system on another system that runs in a completely different platform. Perhaps there is no way to breed a first generation seedling that will be truly healthy and only in further generation will health arise.