I pollinated one of my hybrid rugosa the other day, not knowing much about the cross… it just seemed like a good idea at the time, with some wichurana pollen… then I went looking on HMF to cross check this cross with their database… I found ‘Max Graf’ and followed that through to ‘Kordesii’ which has proven a valuable tetraploid breeder, as everyone here would know, with many descendants. So I began wondering whether anyone else had done this cross, and if not, why not, and if so what kind of results showed up? Do the resulting progeny always turn out ‘sterile’ as ‘Max Graf’ is reputed to be? In the back of my mind I was thinking a more fertile diploid might be produced if the cross was repeated enough times without having to rely on chance events like the formation of diploid pollen or artificially induced chromosome doubling… shrugs Means nothing here until it takes and I have seedlings… just thinking out loud.
I planted a new Max Graf last Fall and this Spring I polinated about 50 Max Graf flowers with My Stars and have three hips almost ripe. Will probably use Don’s procedure to extract the seeds. Time will tell if I get anything out of it or not. Next year I plan to have a lot more flowers to polinate. Thanks to David Z. for informing us that Max Graf has some fertility.
Patrick
What a great idea Simon! Sometimes I think we fear going back to the species will take too much time and generations to get what we would like. We often use and reuse the same lines bringing in more and more modern germplasm and soon we often find the traits we long to bring in no longer are there (strong disease resistance, hardiness, etc.). I tried to recreate the Grootendorst cross between rugosa and polyanthas and got lots of seedlings, but most were weak and didn’t survive. Only a handful out of thousands made it to maturity and only one has a bit of fertility. It is a single with narrow cupped contorted petals. It makes a limited amount of little round orange hips. Each year I try to smother it with pollen and collect the seeds and see what comes from them. Very few germinate and so far out of those that have they have been weak. I won’t give up too easily. I may just need to smother it with different males and try it more as a male. I have some other species hybrids with limited fertility I do the same thing with.
It will be exciting to learn what your seedlings grow into Simon. Dr. Peter Ascher from the U of MN, a really inspiring geneticist, often encouraged that with wide crosses it is very important to use a diversity of parents of each species when trying to make the interspecific cross as that some combinations may have greater likelihood for producing offspring with better fertility. I used that idea for the rugosa x polyantha crosses and got that seedling I call Swan (it is my ugly duckling that someday will produce a beautiful swan).
That is fantastic Patrick for your hips on ‘Max Graf’!!!
I should try Don’s technique on seeds of Swan, after practicing on some other seeds of course first!!!
I think there is a lot of potential too in Rosa arkansana that we haven’t unlocked. Even though Morden used it to generate most of their roses, many of their roses are disease prone and are not hardy enough for us in the Twin Cities. I suspect they have lower humidity and less disease pressure and with reliable snow cover they don’t have to worry as much about winter survival even though their air temperature is colder. I have a really nice stippled R. arkansana from Morris MN and descendants that are hardy and much more disease resistant.
Starting new lines from species I think is an investment some of us need to keep exploring as well as of course working with modern germplasm to better combine the great traits we already have across that material as well.
David
Pocajun, WOW!, well done, show us pictures if you get seedlings!
Simon,
Apparently you aren’t aware of my Rugwich 1. It is a cross of Rosa rugosa ‘Ottawa’ and Rosa wichurana. 'Ottawa is an insect resistant selection from seed obtained from Hokkaido, Japan. The prostrate plant produces single, medium pink (a shade less than ‘Max Graf’), 40 mm. diameter flowers. The foliage is more rugose than ‘Max Graf’. This leads me to believe, although most of the literature says otherwise, that Rosa wichurana is the pistillate parent of ‘Max Graf’.
Rugwich 1 appears to be not quite as vigorous as ‘Max Graf’. Initially, the plant was somewhat susceptible to chlorosis, but it doesn’t have that problem now that it has been relocated to the Devonian Botanic Garden. I haven’t worked much with it, but the pollen appears to have no viability. The lack of fertility in hybrids of Rosa rugosa and Rosa wichurana is also what Texas A&M University discovered in their work with them.
I absolutely agree with you that more work should be done developing hybrids of Rosa rugosa and R. wichurana. This should be done, especially of course, to develop disease resisant roses. Since there is a problem developing hybrids with fertility, my current strategy is to use Rugosas having another species in the parentage to see if this makes a different. This year I used ‘Carlos Dawn’ and ‘Schneezwerg’.
David’s comments about using Rosa arkansana more in breeding programs, I also agree with. Currently, I have one Rosa gallica ‘Tuscany Superb’ x Rosa arkansana selection that should bloom for the first time next year. The shrub is beautiful (dark green foliage), short, compact but viciously thorny. The idea of this breeding program is to develop a type of rose (tough, short, disease and drought resistant) specifically for the northern Great Plains region. I believe this is the first time a breeding program has been consciously planned to fully take into consideration the effects of the vagaries and plant growing conditions of the climate in a specific geographical area. It’s done, of course, by using a native species to that geographical region and another type (Gallica) of rose that is also very well suited to grow in that area.
David wrote: “Starting new lines from species I think is an investment some of us need to keep exploring…”
I cannot agree more!
And with the right species it is very very fascinating.
Particularly when species hybrids are combined uncovering fantastic more than expectable diversity.
I have first blooms on a few 2008 crosses seedlings involving rugosa and wichura derivatives. Fertility untested but more than probable as some have 2003 and later crosses seedlings involving rugosa and wichura derivatives higher in pedigree tree.
These lines are fascinating with very nice foliage, interesting flowers plus fantastic combining potential.
The further from the original species crosses the easier to get fertile offsprings.
Specially in crosses involving four different species.
Hi Paul,
No, I wasn’t aware of your rugosa x wichurana hybrids. I just found it on HMF this afternoon though I didn’t know what ‘Ottawa’ was. Any chance of putting some images on HMF with it?
It’s difficult choosing species suitable for my area as there are no Rosa sp. native to the southern hemisphere. So I’m collecting species I have seen do well here, such as bracteata, gigantea, longicuspis, multiflora, wichurana, rubiginosa, laevigata, rugosa, and banksiae, but it’s always going to be a compromise. We don’t need winter hardiness traits. We need heat and humidity tolerance traits and these species seem to tolerate both well (rugosa is not so great on mainland Australia as its foliage burns easily but it does nicely here). I’d like to get roxburghii ‘plena’ and clinophylla some time in the future to try as well. Gallica varieties, in general, do not do so well in many parts of Australia but seem to do quite nicely down here in Tasmanian. It gets cold enough here to induce dormancy so they flower better and are healthier too. In addition to the rugosa hybrid (‘Scabrosa’) that I have already pollinated I intend to pollinate ‘Ann Endt’ (R. rugosa x R. foliolosa), with wichurana pollen. I’ve done test germinations of both variety’s seeds this season and they have germinated very easily. ‘Golden Chersonese’ (a ecae hybrid) produces hips for me too, so I was thinking of introducing this onto rugosa as well. This cross failed on me last season, however, so if it doesn’t work this season I’ll scratch that one. Wichurana isn’t completely disease proof here but rugosa is. I didn’t know about the rugosa x wichurana connection with ‘Max Graf’ resulting in ‘Kordesii’ before so was just wondering why more people hadn’t repeated this?