Search found 1327 matches

by Karl K
Wed Jul 08, 2020 4:11 pm
Forum: Rose Hybridizers Association Forum
Topic: Handling cold-hardiness
Replies: 10
Views: 425

Re: Handling cold-hardiness

I live in the low desert in southern California. Cold hardiness is not an issue here, but the subject still fascinates me. I remembered one of Percy Wright's non-rose experiments that may be worth a trial. I can't do it down here, but maybe someone in the north would give it a shot. Simply stated, W...
by Karl K
Fri Jul 03, 2020 7:23 pm
Forum: Rose Hybridizers Association Forum
Topic: Handling cold-hardiness
Replies: 10
Views: 425

Re: Handling cold-hardiness

Breeding for hardiness: Early to bed … Bugnet: The Search for Total Hardiness (1941) "I have often noticed that half-hardy plum or apple trees here, unhurt by December 1, passed unharmed through the rest of the winter no matter how intense the cold. http://bulbnrose.x10.mx/Roses/breeding/Bugnet.html...
by Karl K
Sun Jun 28, 2020 12:41 pm
Forum: Rose Hybridizers Association Forum
Topic: Rebloomers genes
Replies: 7
Views: 525

Re: Rebloomers genes

Transposons may be active or suppressed. In the Black Mexican sweet corn, the typical color is maintained only so long as the transposon is suppressed. Outcrossing results in variegated seeds and plants. In Four o'Clocks, the suppressed transposon prevent red stripes/sectors from being expressed. Ou...
by Karl K
Thu Jun 25, 2020 5:54 pm
Forum: Rose Hybridizers Association Forum
Topic: Rebloomers genes
Replies: 7
Views: 525

Re: Rebloomers genes

My assumption has been that the climbing sports of rebloomers are just a disruption of the RoKSN gene with the transposon likely excising out in one of the alleles and restoring its function. David, Another possibility is silencing/unsilencing of the transposon. That might account for some of the o...
by Karl K
Wed Jun 24, 2020 1:29 pm
Forum: Rose Hybridizers Association Forum
Topic: Polyantha alba plena sarmentosa
Replies: 1
Views: 146

Re: Polyantha alba plena sarmentosa

I found the article Guillot wrote about the parent of 'Paquerette' and some others. I don't know that this was also the parent of 'Cecile Brunner' and 'Perle d'Or', but it would be a more likely parent than a "pure" Japanese Rosa multiflora. Also, Guillot, Rambaud and Mme veuve Ducher all lived in L...
by Karl K
Tue Jun 23, 2020 12:50 pm
Forum: Rose Hybridizers Association Forum
Topic: Polyantha alba plena sarmentosa
Replies: 1
Views: 146

Polyantha alba plena sarmentosa

I recall a discussion, long time back, about this old and important variety. I have a note on the subject from May 2003: Guillot described one of his R. polyantha seedlings as having an extra row of petals, and added "sarmentosa" to the description. I think this indicates a different growth habit th...
by Karl K
Thu Jun 18, 2020 11:49 am
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

Years ago, Percy Wright did some experimenting with Rosa foliolosa. I was surprised that this southern species even survived in the Great White North. But you never know until you try. I think it was Erlanson who commented that R. foliolosa looked rather like a smaller R. palustris . Maybe the reblo...
by Karl K
Tue Jun 16, 2020 11:27 am
Forum: Rose Hybridizers Association Forum
Topic: Thesis- “Characterisation and genetic improvement in Rose(Rosa spp.) through mutagenesis”
Replies: 4
Views: 263

Re: Thesis- “Characterisation and genetic improvement in Rose(Rosa spp.) through mutagenesis”

Back in my college days ('70s), I worked part time in the school library. One day I went in to find a book cart with a freshly bound set of the Creation Research Society Quarterly. I just had to look. Most of the stuff was thoroughly forgettable. I do remember the one where the author insisted that ...
by Karl K
Sat Jun 13, 2020 2:08 pm
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

There are some species and cultivars that bloom on new growth, without chilling or other encouragement. The lumpy "Rosa arkansana" complex is famous for this habit, and in some races ( R. alcea Greene) are hardy to -60F. Far removed from these in hardiness, the very old "Rosa indica major" reportedl...
by Karl K
Mon Jun 08, 2020 10:59 am
Forum: Rose Hybridizers Association Forum
Topic: hardiest reblooming diploid?
Replies: 47
Views: 1970

Re: hardiest reblooming diploid?

Karl, I'm not sure I want to use a rugosa like Hansa for this purpose because of the potential for delayed remontancy, ie. a lack of juvenile bloom, which makes screening for a low percentage of rebloomers a much more difficult process. I really shouldn't be advocating for 'Hansa' because I know it...
by Karl K
Mon Jun 08, 2020 10:50 am
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

I was reading further in The regulation of seasonal flowering in the Rosaceae, and found this: Control of juvenility in rosaceous trees Several studies have suggested that TFL1 and FT may control juvenility in rosaceous fruit trees. Consistent with findings in other perennials (Mohamed et al., 2010;...
by Karl K
Thu Jun 04, 2020 10:36 am
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

Mol Biol Rep 39(4): 3737-46.(Apr 2012) The Expression Level of Rosa Terminal Flower 1 (RTFL1) Is Related With Recurrent Flowering in Roses Li-Na Wang, Yun-Feng Liu, Yu-Man Zhang, Rong-Xiang Fang, Qing-Lin Liu Abstract We examined the relationship between the recurrent flowering character and the exp...
by Karl K
Tue Jun 02, 2020 1:33 am
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

Another example I had misplaced, involving crosses among geographical races of a single species. Botanical Gazette, 144(2): 231-233 (June 1983) Photoperiodic Flowering Responses in Hybrid Progenies between Latitudinal Ecotypes of Chenopodium rubrum L. Takeshi Tsuchiya, Yoshio Ishiguri Abstract Photo...
by Karl K
Mon Jun 01, 2020 7:54 pm
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

It is useful (I think) to consider rebloom in other plants. For example, A Guide to Bearded Irises: Cultivating the Rainbow for Beginners and Enthusiasts (2012) Kelly D. Norris Cyclic rebloomers (daylength dependent). These varieties complete two distinct cycles of growth — flowering and increasing ...
by Karl K
Mon Jun 01, 2020 7:30 pm
Forum: Rose Hybridizers Association Forum
Topic: hardiest reblooming diploid?
Replies: 47
Views: 1970

Re: hardiest reblooming diploid?

jbergeson wrote:
Mon Jun 01, 2020 11:03 am
Does anyone have ideas for the hardiest non-rugosa diploid that is fully reblooming?
Joe
I don't live in the north, so I have no personal experience. However, I have read that 'Hansa' survives well and reblooms happily in Alaska.
Karl
by Karl K
Fri May 29, 2020 10:51 am
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

I can attest that miniature X Gloire des Rosomanes produces all once-flowering large plants. Such things happen, apparently just to remind us of how little we really understand. But if the old records are correct, 'Gloire des Rosomanes' was seed parent of 'the reblooming 'Géant des Batailles', and ...
by Karl K
Tue May 26, 2020 9:58 pm
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 28
Views: 1623

Re: Alternate source for repeat bloom

Paul Barden has made posts in the past about Autumn Damask (and Portlands...rebloom mechanics would be the same) and said when crossed with modern (so china derived) that the offspring were once bloomers and wouldn't start blooming until their second year. Also rebloom among Autumn Damasks/Portland...
by Karl K
Tue May 26, 2020 11:34 am
Forum: Rose Hybridizers Association Forum
Topic: Yellow blend rugosa hybrid
Replies: 22
Views: 1163

Re: Yellow blend rugosa hybrid

You may find this article useful if you are interested in further yellow rose breeding: https://deepsouthdistrict.org/wp-content/uploads/2015/04/Newsletter-13.pdf That is a lovely booklet. I may add that Prof. Allard (1900) raised a semi-double seedling from 'Harison's Yellow' that had the color an...
by Karl K
Sat May 23, 2020 11:05 am
Forum: Rose Hybridizers Association Forum
Topic: Multiflora Rose review
Replies: 6
Views: 602

Re: Multiflora Rose review

American Rose Annual 49: 159-164 (1964) Stock-Scion Relationships in Roses Griffith J. Buck ...it has been observed that when the same scion variety of hybrid tea rose is grafted upon different understocks there is definite understock-stem effect upon scion growth. If understocks with chilling requi...
by Karl K
Thu May 21, 2020 10:56 am
Forum: Rose Hybridizers Association Forum
Topic: Is pollen's DNA the same on all flowers of a plant?
Replies: 7
Views: 534

Re: Is pollen's DNA the same on all flowers of a plant?

Some flowers on a given plant have more or fewer petals and different coloration. The cause doesn't seem to be cultural--that is, different amounts of sun on that flower, nor different amounts of water on the petal, nor insect damage. Is the genome of two flowers on the same plant identical or woul...