Dead End Blotch?

Technique Flower Initiation
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41

Thanks all for the kind comments!

Warren, I don’t have many specific roses to mention that resist the blotch since I am mainly breeding Hulthemias with my own seedlings. However, I can say that ‘Double Knock Out’ seems to resist good blotch formation, so it will probably take 2-3 generations using it to get something good. However, I should also say that if you make enough crosses, something good might still show up. One of my best Hulthemias came from a cross from a variety that seemed reluctant to produce good blotches. You have to experiment to see what varieties allow good blotch expression.

42

KO and DKO seem to breed a heavy white eye zone. I was pollinating Trumpeter today with some random stuff, and I noted that, like Anytime, it haze that anthocyanin type eye zone. My guess is that roses heavy in anthocyanin and persian yellows pass on the eye better than something such as Knock Out. Like I sated before, Art Deco, possibly one of the most anthocyanin-rich multifloras to date, also has a dark eye zone. I am not saying that this would typically breed eye zones, but it seems to be a more smooth transition than using something that heavily breeds white eye zones.

43

That makes plenty sense! …err if ya can predict such things.

:O)

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Yeah, of course. Trial and error. Sharing helps, lol. Looking at dominant lineage patterns helps, too.

45

Sharing info helps MASSIVELY, to be sure !!

I was gonna mix Eyes For You with KO / DKO this spring (Sept. onwards for us), but maybe not so keen to do this now… might give it a try… err … and might not.

46

Maybe I should invest in a plant of Carefree Beauty instead, and add EFY pollen onto that.

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George I used Carefree Beauty last spring as a pollinator and what is germinating now has a bit of PM showing, I thought it was the silver bullet rose ??

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George, when I used DKO, I only used it as a pollen parent on two roses. One was on Raven x Preference, and the other was on Remembrance. I knew that going against the grain, so to speak, was futile because of how dominating KO and DKO seem to be. I will go one more generation with my Remembrance x DKO seeding before I try anything more direct.

Which reminds me, Remembrance would be a great rose to use with Bull’s Eye/Eyes for You. It has the anthocyanin eye mark from Trumpeter and the heavy foetida influence from Southampton. Remembrance’s dominant trait is its ability to dwarf its seedlings.

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Yeah if I had Remembrance here I would use it…I don’t think it is downunder, not to worry. I had Brown Velvet and stupidly threw it out!!

I have no clue about Carefree Beauty as a breeder, but it apparently does have remarkable BS resistance itself (at least in some North American regions)…the goal is to see if I can infuse that to EFY offspring, which in my location shows severe BS issues :O(

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…err… of course the other part of the goal is to see if the hulthemia eye transmits efficiently / substantially into the Carefree Beauty offspring when EFY is mixed with it.

51

[quote=ldavis]

I see that Art Nouveau is not a stripe in the usual sense, (ramdom breaks in pigment expression), but a developmental segmentation mutant. Looks like petaloids with the dimple in the outer edge and the yellow streak going to the base. This certainly could give some cool effects.[/quote]

I don’t know how ‘Baron Girod de l’Ain’, ‘Roger Lambelin’ and ‘Modern Art’ came to be, but DuBreuil (1873) discussed how variegated varieties could be produced.

“In July 1867 I paid a visit to the garden of a judge at Bagnéres-de-Bigorre. He showed me several standard Roses, and among them a Geant des Batailles, some of the dark red flowers of which were marked with numerous spots of a pale rose colour. I remarked the same peculiarity in varieties with paler flowers, such as General Jacqueminot. All were in a very fine condition of growth and presented all the other characteristics peculiar to the different varieties. Monsieur X. assured me that this variegation was permanent, and that it was capable of being perpetuated by budding. On inquiring what could have given rise to this singularity, he informed me that having been obliged, when budding a few years previously, for want of better, to use some buds which had no apparent eyes; these nevertheless sprouted and produced flowers, all of which exhibited the peculiarity described, and which he attributed to the imperfect conformation of the buds which he had employed. He then repeated the experiment with the same result, and he now produces this variegation at pleasure by operating in the manner described.”

Though the change can be maintained by budding, it is doubtful that it would be hereditary.

BTW, Monsieur X was almost certainly Zenone Zen.

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I might suggest that there are different layers of cell giving rise to the auxilliary axillary buds at the sides of the absent eye. This might lead to the observed mutability. I don’t know enough about what is precursor to what in the generative tissue of a rose flower. It is well worked out in arabidopsis and some other plants but I’m not sure for roses. It may be epigenetic, or not, and still not pass to the next generation if gametes are produced from a different tissue layer than petals. But petaloids are modified stamens so that isn’t a really great idea I guess.

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This reference might be useful here: http://www.amjbot.org/content/87/3/355.full

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Larry and Simon,

Zen’s results are puzzling. The possibility that mutations trapped in inner cell layers may be revealed in under-developed axial buds has some merit. The Southern Cultivator’s comment, “…that the results of experiments differ in the case of different Roses” seems to support this possibility. Also, the fact that when a particular clone loses the variegation, it can be restored by repeating the budding.

However, how could different varieties yield similar variants? E.g., ‘Geant des Batailles’ and ‘General Jacqueminot’. If there is a “confusion” in differentiation, that somehow some of the cells in the petals “think” they are stamen cells, the coloring might change appropriately. Cook (1926) described such occurrences as “metaphanic variations”, and gave the Green Rose as an example of petal/sepal uncertainty.

But why would such a specific type of uncertainty affect only the petals? Of course, none of the sources I’ve found mentioned leaves, so there may have been some alteration there as well. This also would not explain Burbidge’s statement (1877), “the blooms were different in form, size, and colour, from the varieties whence the buds had been taken, and these new characteristics become intensified with the age and vigour of the plant.”

Darlington and Mather (Elements of Genetics, 1969): “Most old vegetatively propagated plants such as pelargoniums and potatoes have become chimaeras owing to somatic mutation at some time in their history. When they are propagated from root-cuttings (or from disbudded tubers) shoots grow out that conceal inner layers which reveal the chimerical structure and the ancient mutations of these plants.”

That seems like reason enough to try root cuttings of roses.

‘Striped Baron Giron de l’Ain’ differs from ‘Baron Girod de l’Ain’ in a way that does suggest a change in a chimera … that is, a “mutation” in L1 of Baron being present in both L1 and L2 of Striped Baron. If so, then the original ‘Eugene Fürst’ might be recovered from a root cutting. And also if so, some shoots might bear white flowers. Would the petals be even more deformed than in Striped Baron?

I just don’t know. So, if someone is budding roses, it would be worth an experiment to look for some buds that appear to lack an “eye” just to see what comes up.

I’ve already mentioned this in another thread: Hall, et al. (1986) discussed how they isolated a thornless mutation from the chimerical ‘Thornless Loganberry’ by meristem culture.

Karl

55

Since reading this article I’ve had a theory that by taking a sported rose variety and removing apical and primary axillary buds to force the development of secondary axillary buds it might be possible to ‘induce’ heritability by causing the reorganisation of somatic mutations into the germ line. I thought that ‘Burgundy Iceberg’ could be ‘induced’ to breed like a burgundy instead of its white parent by forcing the development of these secondary axillary buds. I started thinking that there was different forms of white and that white, such as in ‘Iceberg’, is something like an epistatic effect and it was actually a pink or burgundy rose under a white top coat, so-to-speak, and that by forcing these secondary axillary buds to grow in ‘Burguby Iceberg’, what ever was turning the epistasis off might be ‘relocated’ into the germiline and become inheritable and more stable. I’ve not tried this yet with BI because I decided to try and find something that would have a more identifiable phenotype to prove it. So I chose stripes. By choosing a variety that has sported stripes and treating them to forced secondary axillary bud development and then pollinating from flowers produced on these stems I figured it would be possible to demonstrate a transition from somatic mutations to germ-line mutations by the pressence of stripes in the progeny. I need to try and find a striped sport that I can choose (and I disllike ‘Harry Wheatcroft’). I have two plants of the striped Delbard ‘Maurice Utrillo’ but I need to find evidence stating it is a sport… this one conerns me, however, as the stripes seems to fade in the heat of summer as though virally induced which would introduce the added variable of possible infection rather than inheritance. The fact that stripes made it intro the germ line of roses like ‘Ferdinand Pickard’ seems to suggest that this should be possible and that this might be a possible mechanism for the change. Any ideas?

56

Simon,

Sometimes stripes and other types of variegation are due to transposons (jumping genes). The cell may or may not recognize the transposon, and silence it – along with whatever other genes might be located near it.

The “Black Mexican” sweet corn is an example. The strain normally bears uniformly slate-grey kernels, but when it is crossed with a white corn some of the kernels are white with dots of black. Plants raised from these dotted kernels also show variegation. Some silks are white (like those of “Black Mexican”) while others are pink or light red (typical of the white corn). I haven’t made the cross, yet, so I don’t know whether the degree of variegation is affected by heat.

Another case that looks like a transposon might be involved was reported by Correns. When a white-flowered Mirabilis jalapa is crossed with a pink or yellow variety, the offspring have flowers streaked with red. The white-flowered strains are nearly true-breeding, but a few percent show a hint of striping.

I have noticed that among striped roses there are differences in the relative stability of the differently colored sectors of the petals. In ‘Papageno’ and ‘Striped Queen’, for example, the red sectors tend to stay red, while the non-red areas are frequently interrupted by red. “Legacy of Tomeso Kawamoto”, on the other hand, is just the reverse. Finally, the two regions may be approximately equal in stability. I think I have an example of the last type, but I can’t remember the name.

Whether these striped roses carry a transposon is an open question. It may be that a gene involved in pigment synthesis happens to be located near an unstable boundary between heterochromatin and euchromatin. Either might be inherited.

‘Candy Stripe’ is a striped sport of ‘Pink Peace’, if you need a known sport.

Karl

57

I know ‘Papageno’ passes on stripes. This is a seedling (OP) I have from it with good striping:

[attachment 899 OPPapageno1.jpg]

Actually… I just remembered I have Flower Carpet ‘Pink Splash’ which is a striped sport to play with!

58

I just found a paper that may be of interest: Genetic and biochemical characterization of a “lost” unstable flower color phenotype in interspecific crosses of Nicotiana

“The earliest studies on the genetics of N. langsdorffii and N. sanderae allowed an identification of the several genes involved in corolla coloration (Smith, 1937a). Continuation of these early studies identified a genetic instability in the flower color genes in progeny derived from these crosses. This instability was first observed in 1939 and was widely studied. The early papers described the appearance of the variegated phenotype in the standard N. langsdorffii X N. sanderae crosses. At least six different variegated lines were isolated from this material. These different lines expressed variegated sectors of differing sizes which have been interpreted as differences in the timing of the sectoring event (Smith and Sand, 1957). Subsequently, clones of one variegated plant, variegated-1, were tested for temperature sensitivity during development (Sand, 1957). The sectoring frequency was highest at 80°F (the highest temperature tested) and these studies also demonstrated a positive correlation between the culture temperature of the parental clone and the frequency of sectorial events in the progeny. Thus variegation in the N. langsdorffii X N sanderae crosses result from reversible changes in the functional condition of a gene that results in alteration of flower color from red to white. This alteration is also influenced by environmental factors.”

This reminds me of a similar case involving camellias reported by William Herbert in 1837:

“The striped sorts have usually more white in their flowers when they flower earliest in the spring, and it seems that the seed ripened earliest in the year is the most apt to yield white or pied seedlings.”

In this case, low temperatures favored variegation.

If these cases can be applied to striped roses, it would be worthwhile to learn which temperature range favors striping in the varieties being used as parents.