William Baffin as pollen parent

I have 47 seedlings of My Hero x William Baffin and 45 seedlings of Hot Wonder x William Baffin. So far 20 of the Hot Wonder x William Baffin seedlings have flower buds on them while none of the My Hero x William Baffin do, even though they germinated earlier and are the larger seedlings.

I

I have found that although ‘William Baffin’ definitely tends to produce offspring that do not exhibit juvenile remontancy, its not always the case. You can occasionally make a cross that shows a large percentage of juvenile repeaters. It won’t take long for ‘William Baffin’ characteristics to shine through in these seedlings. You’ll soon know if they are Baffin hybrids or not, but I suspect they are.

Working with L83 is a very similar situation: most seedlings from most crosses do not bloom in the first year. If they do, they usually don’t flower until quite late in the year. Its a curious phenomenon.

Paul Barden

I stopped using William Baffin after about a dozen hybrids were all non-juvenile-recurrent. Only a few grew to maturity (they vary widely relative to hardiness), at which point some became recurrent. I believe that this form of recurrence comes from R. laxa. Possessing it does not enhance the percentage of juvenile-recurrent offspring in backcrosses with modern roses, but it sure makes them easier to work with. I am considering using WB as a pollen parent again this year with yellow female breeders.

I had a mini (Hot Tamale) X WB hybrid that took several months to bloom, but did so as a mini. To look at it, you would assume it was a normal mini with juvenile recurrence. I let it self-pollinate, and got a couple of truly juvenile-recurrent mini offspring.

Obviously, my experience (relative to juvenile recurrence in the William Baffin F1) was different from Paul B

Further to Roger’s comments (thanks for these thoughtful remarks, Roger!) I should mention that my recent crosses using L83 were extremely fertile and so I was able to grow over 100 seedlings from each of three crosses. For each cross, I kept the best 50-70 (based on vigor, health and attractive foliage) and grew them on in 1 gallon pots. I would say that in each of these three crosses, approximately one in 25 was blooming by late September or October. I expect to see the remainder flower this Spring at which point I will begin selecting for bloom color/quality. Two of these crosses involved a yellow miniature as the seed parent and the third used a proprietary red shrub called “Penny-trad” I use as a breeder for red and for vigor. (Seedling “Penny-trad” = yellow mini X Austin red shrub)

I haven’t worked with ‘William Baffin’ for a couple of years simply because I saw very little of Baffin’s disease resistance in any of the seedlings. However, I think this had more to do with a poor choice of seed parents than 'William Baffin’s ability to pass on good traits. I will resume my work with ‘William Baffin’ this Spring, working with more of my seed bearing Rugosa hybrids and varieties that have shown superior disease resistance.

Right now my #1 goal is to develop a few strains of breeders that show complete resistance to Blackspot, and I am concentrating on lines that do NOT use ‘Knockout’ and its derivatives. (However, I am testing one yellow ‘Knowckout’ seedling this year to determine its fertility and garden value) It appears that ‘Knockout’ is not a good choice for breeding roses with complex, sophisticated bloom form. IMO we don’t need more five to ten-petaled shrub roses whose most valuable trait is disease resistance. I am finding that some strains of R. wihcuraiana hybrids I am working with have superb Blackspot and Mildew resistance and these lines bring in a wider variety of aesthetic traits. Wichuraiana hybrids also tend to be very easily propagated from cuttings, which is a real asset.

Paul

Hi Paul,

I have a Morden Sunrise x William Baffin seedling from a few years ago that took me by surprise when it bloomed in its first year. It has the classic purplish canes of WB, has virtually no die-back on the canes, is a non-climber with reddish-pink semi-double flowers with a yellow eye. Disease resistance wise the seedling is pretty decent. Last year was pretty wet up here and it held up in my no-spray garden. It looks like a good seed parent, as I have quite a few OP seedlings from it this year. So far that is the only WB seedling that I have kept, but there are a few more in this year’s batch that hopefully will show some promise.

I have been using John Cabot in more of my crosses. I have a Luis Desamero x John Cabot seedling from last year that has not bloomed yet, appears to be a non-climbing mini, is very clean so far, and again shows no die-back on the canes. JC is probably a bit cleaner in my climate, over winters as well as WB, the blooms last longer, and there does seem to be a bit of a second flush.

Liz

The My Hero x William Baffin seedlings definitely have WB characturistics, they are upright, vigorous and very thorny. It

When I compare the Hot Wonder seedlings that are blooming with the ones that are not, the ones that are not are more vigorous and the stems are a little more stout. I don

This is really interesting. Lack of juvenile bloom seems common with many of the Explorer types that have R. x kordesii in them. Some seem to provide more non-juvenile recurrent offspring than others. ‘William Booth’ for instance seems to give much more juvenile recurrent offspring than ‘William Baffin’.

I suspect this is due to the rugosa influence in the background of R. x kordesii. Rosa rugosa is adapted to be a repeat bloomer in the wild as a species. There is the major gene for recurrency in place that is likely a gibberellic acid related gene as proposed and the same major gene in modern roses as crosses of it with modern roses often results in repeat blooming hybrids (i.e. Grootendorst roses, ‘Topaz Jewel’, etc.). THere are then also other, minor, genes that contribute to lack of juvenile recurrency until the plant is large enough to support flowers because it isn’t to the plant’s advantage to bloom before it grows enough and carves out a niche for itself in its environment. SOme of these minor genes may last into maturity limiting strong repeat bloom. The repeat blooming China roses seem to be selections out of the wild from one time bloomers and perpetuated through cultivation. Repeat bloom is not found it sounds in the wild for those roses. There hasn’t been the opportunity for selection for minor genes that contribute to lack of juvenile recurrence to be favored in the wild. It seems that many of the hybrid musks also have long lanky growth and poor juvenile recurrence at first, but overcome it sooner than the rugosa backgrounds. It also seems that perhaps descendants of the supposed repeat blooming R. wichurana ‘Basye’s Thornless’ may also be similar. It may have the recessive alleles for the major repeat bloom gene, but not express it that well in itself because of these minor, modifying genes. Dr. David Byrne developed diploid populations of ‘Old BLush’ x (‘Old BLush’ x ‘B. Thornless’) and has much less than the one half typical repeat bloom expression of ‘Old Blush’. Perhaps these minor genes may be part of the cause if what people have said about the minor repeat blooming nature of BT is true (I just got a cutting of it for the first time last fall from a friend). It seems like ‘The Fairy’ can give poorly recurrent offspring too and perhaps it has some minor genes that somehow can get re-arranged in different dosages in the offspring to contribute to much less repeat bloom than in ‘The Fairy’.

What do others think about modifying/‘minor’ genes that suppress the major gene for repeat bloom? Have you experienced suppression in crosses with other backgrounds?

Sincerely,

David

The repeat blooming China roses seem to be selections out of the wild from one time bloomers and perpetuated through cultivation. Repeat bloom is not found it sounds in the wild for those roses.

David, are you referring to R. chinensis spontanea here? Is there some research on this that you can point us to?

Crosses with ‘Basye’s Legacy’ result in many once blooming seedlings. Kim Rupert’s ‘Indian Love Call’ is a thornless, once blooming shrub bred from ‘Basye’s Thornless’. If ‘Indian Love Call’ is used as a parent, a high percentage of the seedlings will also be once-blooming. I have seen evidence that suggests this phenomenon will continue for at least one more generation.

Moore’s ‘Out of Yesteryear’, a R. bracteata hybrid, also breeds a fair number of non-remontant seedlings regardless of how remontant the other chosen parent is.

There seems to be a whole lot we don’t know about how remontancy works in roses. Is it not generally accepted that repeat blooming in roses is regarded as the breakdown of a gene or genes that are intended to limit it to one bloom period early in the season?

Paul

David, a lot of this will be old news for you, because we have discussed this issue so much, but it may be new to many of our readers:

I have also seen a suppression of juvenile bloom in some polyanthas. I got once-blooming offspring from Robin Hood OP. Some began to bloom lightly in the late season, once mature. I have many controlled crosses with the polyantha

Roger,

No need to apologize! Although I can only speak for myself, I expect we are all VERY appreciative of your input. I know I am learning things from your posts and am thankful for them.

For me, rose breeding is more art than science, so my knowledge of rose genetics is only basic stuff. Your posts are expanding my knowledge and I thank you for that.

Paul

Thanks, Paul! When you and others discuss the results of your crosses, that information is the most valuable thing. That

I second what Paul said. I appreciate all of the comments that everyone has made. Because of them I have a better understanding of what

I just checked my seedlings, there is (1) Champlain x John Cabot and (4) Carefree Beauty x John Cabot seedlings with flower buds on them. So John Cabot most likely isn’t homozygous for non-juvenile bloom and is capable to pass that trait on to some of it’s seedlings.

Thank you Roger!! I really learn a lot from what you share and the fun times we have had brainstorming these questions together. I am very excited about your soon to come out article in that special issue of Floriculture and Ornamental Biotechnology on this very topic where you present your vast data from your crosses involving different species roses. The abstract is online and located at this point at: http://www.globalsciencebooks.info/Journals/images/InPressList_Abstracts.pdf

Thanks again!!!

Sincerely,

David

Roger E. Mitchell II (USA) The Inheritance of Juvenile Recurrence in Rosa Species Hybrids

ABSTRACT

Original Research Paper: The current market for roses demands that new cultivars bloom throughout the growing season. The form of recurrence found in most modern roses can be termed juvenile recurrence, because bloom begins only months after germination. Previous studies have observed that juvenile recurrence is conferred by a recessive allele at a single locus. Most species in the genus Rosa have not yet been used to produce commercialized hybrids, in part because they carry the dominant allele for non-recurrence. Furthermore, only a few species have been tested for their effect on recurrence when used for hybridization. This study investigated the inheritance of juvenile recurrence by crossing several hardy tetraploid species and near-species hybrids with modern roses, and then backcrossing the resulting hybrids with modern roses to recover recurrence. For all species, and all but one first-generation hybrid, juvenile recurrence was recovered. This suggests that using non-recurrent species in a rose breeding program is feasible. The numbers of recurrent and non-recurrent second-generation backcross offspring produced by each first-generation hybrid varied. Some progeny groups did not differ significantly from the

theoretically predicted 1 recurrent: 5 non-recurrent ratio, while the number of recurrent offspring was lower than predicted in the rest. The ability of some species and near-species hybrids to produce some late blooms did not affect the frequency of juvenile recurrence in the second generation.

Paul, it is nice to know that John Cabot is throwing juvenile blooming seedlings. I have quite a few Alberta x John Cabot seedlings this year. I’ll keep track of how many flower this year. This is my first year using Champlain and it is nice to know that juvenile blooming seedlings are possible with it as well.

Liz

Hi Liz,

Let us know how many of the Alberta x John Cabot seedlings have juvenile blooms so we can compare your rate versus mine. But we should be careful and make sure these seedlings have John Cabot characteristics first before we make any assumptions, just like I need to do with my Hot Wonder x William Baffin seedlings.

I think it is safe to assume that the seedlings that don

Paul G said: “1) John Cabot and William Baffin do have the capacity to pass on juvenile bloom to their offspring and the seedlings are hybrids with them. Paul Barden noticed that he had about 1 out 25 with juvenile bloom with his seedlings.”

Actually, that statistic was specifically referring to work with L83, not ‘William Baffin’, just to be perfectly clear on this matter. I have not raised more than 20 seedlings of any ‘William Baffin’ cross yet, although this year I have a few crosses that will likely exceed that number.

I am very careful with emasculating seed bearers and I think you would agree if you saw the L83 crops that all the ones that expressed juvenile flowering were conspicuously L83 progeny. In my case, with the L83 seedlings, I believe you can eliminate the possibility of these being open pollinated or self pollinated seedlings. L83 expresses itself quite strongly. I have so far used L83 only as a pollen parent, so any op or selfs would not be expressing L83 characteristics.

There is one other possibility that I believe I see occasionally: apomixis. I have made several attempts with my easiest seed bearers to create R. sericea ptericantha hybrids, but in every case what few seedlings I get all look almost identical to the seed parent and all bloom when very young, showing no ptericantha traits whatsoever. It has been speculated that apomixis is the mechanism at work here.

Regards,

Paul

I’m sorry I miss-quoted you Paul. I was trying to make it look like I was paying attention to what people were writing and I got it wrong anyway.

That’s a good point about apomixis, one that I hadn’t considered.

The only way I will know for sure if my seedlings are hybrids is to wait until they get a little bigger and see if exhibit any of William Baffin or John Cabot characteristics. Right now it