Reciprocal crosses

Rose Genetics Ploidy Level
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1

Nicolas: Hybridizing Rose Species (1933) …my experiences of many years concur with Mallerin’s of France, Lambert’s of Germany, Dot’s of Spain, and other practitioners, that the species is more easily and quickly “cracked” when used as pollen parent; its imprint at the first generation is generally more subdued, or to be more correct, the percentage of the mother type, with, of course, a more or less pronounced species influence, will be much larger than the species type, and these mother types will save time in bringing the desired finished product. For instance, a cross of Hortulanus Budde x R. Moyesi gave me slightly modified Hybrid Tea types where Moyesi was only recognized by the weird red single blooms and smaller foliage, while one almost totally mother type revealed the pollen parent only by the queer bottle shape of Moyesi fruits. The reciprocal cross (R. Moyesi X Hortulanus Budde) produced plants almost as uncouth and crude as Moyesi.

Wichura on Hybrids (1866) p. 73 Wichura confirms Gaertner in the assertion that where hybrid pollen is used for the impregnation of simple or complicated hybrids, as also in pure species, there is a great predominance of individual forms, while hybrid ovules impregnated by the pollen of pure species, even in the most complicated combinations, give very uniform products.

At first glance these two items appear to be contradictory. However, more recent research suggests that species are more than mere assemblages of unit characters. A species may appear fairly uniform across a population, while concealing a wealth of genetic diversity. How this is managed is a complicated subject, but may be analogized as a sort of “program” that sits between the genotype and the phenotype. This program can buffer the phenotype against most of the familiar environmental stresses, while also buffering against the familiar genetic diversities of the population.

In most garden plants, to the contrary, breeders usually favor the greatest divergences from the “type”, which leads to a breakdown of the buffering program. Or, to change metaphors, much plant breeding involves removing the shock absorbers and springs of the plants’ suspension system, thus allowing the phenotype to bounce along in parallel with the genotype.

I’m not sure how to reconcile the two reports. I’m not even sure they involve the same underlying mechanism. Has anyone made such reciprocal crosses?

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I have not made the recipricol, because I often work with canina types… which are messy, but I find these infobytes really interesting. I had to use R. virginiana as pollen, too, because it refused to set hybrid seed. I think, though, that in both cases, the hybridity is very pronounced, which is fine with me.

3

While I’ve attempted reciprocals, I’ve often found using the species pollen on the modern rose results in many more actual crosses and tremendously greater germinations, period. NOTHING I ever put on Fedtschenkoana resulted in seed, but using its pollen has provided many definite hybrids. Hugonis seed haven’t been good germinators for me, but putting its pollen on 1-72-1 resulted in the hybrid I play with regularly. Using the hybrid for seed provided me some seed, ostensibly with the foreign pollen applied, but only ONE seed has germinated. There have been quite a few more germinations using its pollen on other moderns. I experienced the same with Nitida, with only one seed germiniating from its pollen on Orangeade, and absolutely nothing using it for seed.

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[quote=PacificJade]

I have not made the recipricol, because I often work with canina types… which are messy, but I find these infobytes really interesting. I had to use R. virginiana as pollen, too, because it refused to set hybrid seed. I think, though, that in both cases, the hybridity is very pronounced, which is fine with me.[/quote]

Right, Caninae species would not be good tests for reciprocal crosses anyway because of the ova and pollen have different numbers of chromosomes. Skinner did get seedlings from R. virginiana alba.

American Rose Annual (1956) 41:123-125

New Approach to the Breeding of Hardy Roses

Dr. F. L. Skinner, Dropmore, Manitoba

“Rosa virginiana was one of the American rose species that I used many years ago with rather indifferent results; however in the spring of 1950 I had in bloom, in pots, plants of R. damascena Celsiana, R. d. rubrotincta and a double white form of R. alba as well as a plant of R. virginiana alba. The flowers of the latter were fertilized with the pollen of the three old roses and from the seed secured about twenty seedlings germinated in 1952. Two of these seedlings that flowered for the first time this year had double flowers, one had white flowers resembling R. alba while the other had clear pink flowers like Celsiana in form and only slightly smaller; the foliage of all these R. virginiana alba hybrids is clean looking and nice. Pollen from these hybrids was used this summer on some of the old roses with apparently satisfactory results.”

Maybe there are differences in crossability among clones of R. virginiana.

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Kim,

I have read that seedlings, flowering for the first time, are more receptive of foreign pollen. Have you (has anyone?) raised R. fedtschenkoana from seed? Or other species?

Karl

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Hi Karl, I’ve only raised two or three Fedtschenkoana from seed as that’s all the seed it’s ever given me. Those went to Joe Bergeson last fall. I have two seedling raised Stellata mirifica which germinated last spring. Other than that, no sir, no other species from seed.

7

Oh, I do have Rosa rugosa alba x Baby Love and R. r. a. x Livin Easy, and they both have dominant plant features of each male parent, including foliage shape and color. They should bloom this spring, but I have a feeling they’ll be neon white, based on how on how lime-green both of their foliage is. I dont know how this fits in two these two keepers from that run of rugosa seedlings from 2010.

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You know, you also have the reciprocals which are nearly impossible to make. NOTHING I have ever put on Banksiae lutescens has ever stuck. I’ve only ever found seven self set hips on the whole mound, yeilding six seeds. Only one has ever germinated and that one exploded from the ground in a record four months from planting. None of the other seeds have germinated. Lutescens’ pollen has worked on several things but nothing takes on it. Kim

9

Very interesting Karl. After thinking about it for a while here is my gut reaction.

The reciprocal cross (R. Moyesi X Hortulanus Budde) produced plants almost as uncouth and crude as Moyesi. – Could this be the result of Apomixis.

hybrid ovules impregnated by the pollen of pure species, even in the most complicated combinations, give very uniform products.— Wichuraiana is in the class synstylae which is a major component of modern roses. So even if they were unrelated to wichurana directly most modern roses I think the chromosomes would match and the resulting plant would know what to do with the information. Since many of the genes in species tend to be dominate by nature these would show through easily. In contrast since Moyesi is a Cinnamomeae and this section did not contribute much to the modern rose genetics maybe resulting hybrids are more varied because maybe whole sections of dna can not be read. So in essence maybe some domiante genes are shut off. Breeder in general tend to select a larger majority of recessive genes than nature does. Dominate genes in nature that do not work tend to become extinct.

Another possibility is what is the average rate of cross over in the chromosomes in roses and does it vary with species.

I have not done many reciprocal crosses. Many of the crosses I have tried have only worked one way. I have some Rosa foliolosa hybrids with R. rugosa and it does seem when R. rugosa was used as the seed parent the foliage does take after the rugosa more than foliolosa but still clearly a hybrid between the two. Crosses using Rosa foliolosa as the seed parent seem to be more segregated with three groups with the largest group seeming to be in the middle. But the crosses using R. rugosa as a seed parent are a small seedling sample so I can not make a definitive statement even for this particular cross. Also the R. rugosa used are hybrids so that could have something to do with it. So in this case it does seem at least in terms of leaf characteristics a difference but this could be effected by the small sample taken from the rugosa being used as the seed parent and the fact both rugosas used are hybrid themselves.

On a side note I do have two seedlings of Gala x Rosa foliolosa. One seedling of Rosa foliolosa x Gala. This is an extremely small sample size so it really has no meaning. I got plenty of seed very little germination on these. But they all look like modern rose seedlings. Except for slightly elongated foliage which is similar to the foliage you would see on any of the variegated modern rose I would think these were pure modern roses if it wasn’t for the fact they refuse to bloom. So if this small sample mirrors a larger sample here there would be no difference between crosses.

In the end I think that roses are such a big family it is hard to make solid rules especially when certain groups in this family seem very far apart. And the rules we do find work in almost all cases end up being broken now and again.

10

I have several hybrids between R. virginiana and R. fedtschenkoana from 2007–I even repeated the cross a year later and sent seeds to Paul Olsen, although I never heard what his results were with respect to germination. In truth, I had an abundance of germination to the point where I threw the bags away. I ended up keeping 3 seedlings that were clearly hybrid, most resembled R. fed, and were among the healthiest seedlings. These were finally planted last fall after several years of growth in pots. Two of the three had the more repetitive type of bloom seen in R. fed. I did not try the reciprocal cross though, and at the present time my only R. fed is a cutting that seems to be struggling–I had to remove my mature specimen due to it’s rampant nature (it was simply in the wrong location but was taking over two seedling beds several feet away). This could have been a fun group with which to experiment with congruity back-crossing, which brings me to my next point.

Years ago, I presented a seminar in grad school on congruity back-crossing in beans (Phaseolus) and I did a two-part article on the subject for the RHA newsletter back in the late 90"s summarizing the topic. The concept was that when you do a wide cross between species and back-cross the resulting seedling(s) to each of the original parent species, in the first generation or two you are trying to establish more congruity between the two species and what you are looking for is survival of almost anything–especially those seedlings that have reproductive fertility and can be used in further crosses. You alternate with crossing the resulting seedlings back to both parents in alternate generations so that the influence of both of the original species parents is maintained in equal measure. What was interesting was that in Phaseolus, this technique had been carried out for 10 or 11 BC generations and they kept discovering new characteristics and colors that were not visible in the two original species. The results were truly fascinating. It is unfortunate that when dealing with a species like roses, it takes so long for each generation to mature. Long ago, I had visions of trying this type of cross between R. spinosissima and R. pendulina–brought to mind because I had a Mary Queen of Scots (the R. spin x R. pendulina version). I repeated the original cross both ways and had results from both crosses, but I admit that I lost interest in the topic due to the difficulty of keeping R. pendulina alive. At the present time, I only have a (R. pendulina x Altaica) and a (Altaica x Mary Queen of Scots) remaining. Does anyone out there have R. pendulina pollen? I think I could almost finish the first generation of a BC cross.

Also, over the years, many species seeds have come my way. I don’t think I’ve ever had complete failure of germination with any species I’ve tried–at least one or two seedlings usually resulted. I have to admit that in most cases, these attempts at germination had more to do with academic interest than anything else–I simply wanted to determine the stratification periods for most. A R. arkansana (a rust bucket) and R. setigera were the only ones I kept for personal use unless they were species hybrids from deliberate crosses.

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Two things come to mind about the reciprocity effect. One is that there is a lot of linkage disequilibrium. so the chromosomes tend to hang together one way or the other. With Carefree Copper which is half Austrian Copper, many seedlings are either a whole lot like CC or not much at all like it. There doesn’t seem to be much of a middle way. I have done crosses both ways. More fertile by pollen than as seed parent, but I’ve gotten really similar results ( like CC) out of reciprocal crosses with Carefree Sunshine. And a once-blooming brilliant red single when back-crossed to Carefree Beauty. That it turn is finally giving something with the coloration in a reblooming plant after cross with Rainbow KO and others. I see why Pernet struggled to introgress the yellow.

The second thing is imprinting whereby certain genes are modified by either the mother or father, by methylation of DNA or some such process. SO the gene is not formally a different gene but functionally it is, maybe shut off for a generation or more. Some things get reset with each sexual generation. But some go on longer than that. Sort of Lamarckian inheritance of a particular history.

12

Similar to Skinner’s experience with virginiana… I got seed set on Rosa carolina [other than when using other native’s pollen] only when I used pollen from an “Old Garden” rose, Apothecary’s rose. The seedlings were similar enough to carolina that I’ve doubted their hybridity at times, but there are enough differences that I think it really is a hybrid. I wish it had gotten the double flowers - that would have made it a little easier to confirm.

13

My Coffee Bean x Rosa virginiana has yet to bloom, but the stems and leaf stems are VERY red, in the color of R. virginiana, but the pattern of Coffee Bean. The plant itself is looking to be like a dwarf cinnamonae type. I cant wait for it to bloom, and the plan was to merge it with colorful wichurana-based shrubs. So far, this hybrid is looking to be 50/50.

As for R. glutinosa, it just put on a 1" growth spurt, so I can plan crosses and see how they compare in 10 years :stuck_out_tongue: :]

14

Yeah, that glutinosa sure is “compact” isn’t it ;0) LOL

But seriously, I hope it’ll bloom for you way before 10 years. I think the original one bloomed for me when it was still well under a foot tall. It’s definitely not tall and/or lanky like it’s cousins canina and eglanteria. At full bushy-maturity, for me glutinosa have always been between knee and waist high. I’ll see if I can get a picture of its bare bones so you can see what to expect.

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I remember photos of it. It looked like a compact rugosa with hips like roxburghii, lol. I thought it looked cool. It just looks like it requires some patience to get out those cool genes it carries for growing in mountainous wastelands.

The plant is currently growing in a large pot w/ a salmonberry I raised from seed last year. The salmonberry is winning :] but I’ll transplant them both when it looks safe enough to not have to watch them from danger, since theyre both rare.

As for caninae and all that, pomifera has the most universal plant, compared to all of its kin. Yet, it is not really used…

16

Kim,

That is interesting. It looks like Rosa banksiae is another of the species whose fertility is affected strongly by environmental conditions.

Mansuino (1960) crossed R. banksiae lutescens with ‘Tom Thumb’ in both directions. He lived in San Remo, Italy (coastal).

Paolo Baroni, curator of the Botanic Garden dei Simplici, Florence, Italy, raised three single flowered R banksiae seedlings (two white and one yellow) from a double-flowered variety. “Dr. Fenzi’s note indicates that these varieties were bearing every year a certain quantity of fertile seeds.”

However, Dr. Attilio Ragionieri of Castello, near Florence, Italy, reported that the two specimens he received from that garden did not bear OP seeds (he blamed “autosterility”), and that “Cross-fertilised flowers rarely bear fruits and, more rarely, fertile seeds. The fruits are like a small Pea and when they contain a single round seed some promise of germination is offered, but when two or three small, irregular seeds are produced, they are certainly sterile.”

Could humidity be relevant? Has anyone else had success using Rosa banksiae as seed parent?

Karl

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Karl, relative humidity and temperatures could easily be the issues. In inland heat, you don’t find hips on Iceberg nor Mermaid, but put them in a humid, cool, coastal area and they form hips readily. I never found any self hips on the Banksiae normalis at The Huntington in all the years I searched for them. My lutescens sets the occasional hip and I find seeds in them. Only one has ever germinated, and in only four months from planting. I have the plant, wishing it would flower this year. I found hips on lutescens this spring which yielded a few small seeds, which I didn’t plant as I didn’t want to mess with them in case they took the suggested two years to germinate.

[attachment 1544 lutescenships2.JPG]

[attachment 1545 lutescenships1.JPG]

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My Iceberg here in Oz was exposed to 100F heat last summer and produced over 100 hips.

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Percy Wright: Interactions of Various Rose Species. 1947

“Another principle which has been uncovered is that if a rose of a pure line, that is, a species, is crossed with a complexly hybridized rose, the characters of the pure-line will be dominant. For example, if species A is crossed with species B, and then the hybrid crossed with species C, the resultant progeny may be strikingly uniform and strongly resemble C. On the other band, if A and C were first crossed, then B crossed with the hybrid, the progeny will strongly resemble B. No one, thus, should expect too much in the first generation from crossing a hybrid tea with a species. If the characters of the hybrid teas are to dominate, put their pollen on a hybrid between two or more species.”

Wright doesn’t mention differences in reciprocal crosses, but this observation seems related to the other two statements I quoted.