Search found 1481 matches

by Karl K
Thu May 12, 2022 9:15 pm
Forum: Rose Hybridizers Association Forum
Topic: Gloire des Rosomanes - experiences
Replies: 19
Views: 349

Re: Gloire des Rosomanes - experiences

The GdR plants I've known and loved at the San Jose Heritage had a tendency to sport pale pink blooms, often only in part. http://bulbnrose.x10.mx/Roses/Rose_Pictures/G/gloiredesrosomanes2.jpg so maybe 'Old Blush' was involved rather than Crimson China. I have read so many contradictory descriptions...
by Karl K
Thu May 05, 2022 4:55 pm
Forum: Rose Hybridizers Association Forum
Topic: Pruning and Pollen Viability
Replies: 5
Views: 254

Re: Pruning and Pollen Viability

http://bulbnrose.x10.mx/Roses/breeding/Buck/Buck_stock.html American Rose Annual 49: 159-164 (1964) Stock-Scion Relationships in Roses Griffith J. Buck There is some indication that earlier and heavier flower production is stimulated by grafting.4 The presence of a graft union, even in the case of c...
by Karl K
Thu May 05, 2022 9:23 am
Forum: Rose Hybridizers Association Forum
Topic: Pruning and Pollen Viability
Replies: 5
Views: 254

Re: Pruning and Pollen Viability

I keep looking, but cannot find an explicit reference to ringing affecting pollen viability. But I have found some further information. F. N. Fagan, The Pennsylvania State College—Agricultural Experiment Station 1925: In June of 1922 a few Baldwin trees were ringed in the customary manner, removing ...
by Karl K
Fri Apr 29, 2022 8:16 pm
Forum: Rose Hybridizers Association Forum
Topic: Pruning and Pollen Viability
Replies: 5
Views: 254

Re: Pruning and Pollen Viability

A couple of items: The Pennsylvania State College—Agricultural Experiment Station, Bulletin 230, p. 35 (July 1928) Effect of Ringing Fruit Trees on Tree Growth and Reproduction. Preliminary work was done on the effect of ringing on the viability of the pollen of varieties that are notoriously poor q...
by Karl K
Thu Apr 28, 2022 12:31 pm
Forum: Rose Hybridizers Association Forum
Topic: Pruning and Pollen Viability
Replies: 5
Views: 254

Re: Pruning and Pollen Viability

If pruning of various kinds can reduce pollen viability, it seems to me that the viability might be improved by ringing (girdling, binding). Such a treatment blocks the downward flow of carbohydrates, while allowing the continued upward flow of water and soluble minerals. Of course, I have not found...
by Karl K
Sat Apr 23, 2022 7:30 pm
Forum: Rose Hybridizers Association Forum
Topic: Pruning and Pollen Viability
Replies: 5
Views: 254

Pruning and Pollen Viability

I happened on this paper today. It's one of those strange notes that brings together things don't immediately seem to be related. This paper can be summarized pretty simply: Less severe pruning increases germinability of pollen. At least in Grapes. For more detail: Winkler: Grape Pruning and Pollen ...
by Karl K
Sat Apr 23, 2022 7:26 pm
Forum: Rose Hybridizers Association Forum
Topic: Rebloom
Replies: 24
Views: 3100

Re: Rebloom

A bit off topic, but I came across this long-forgotten item on my web page. I have not found any confirmation of this, but it's interesting how this sort of induced repeat seems to be fairly common in widely different plants. Popenoe: Origin of the Banana (1914) Seeds may be produced in an ordinaril...
by Karl K
Sat Apr 16, 2022 9:48 am
Forum: Rose Hybridizers Association Forum
Topic: A mini sporting to floribunda
Replies: 11
Views: 450

Re: A mini sporting to floribunda

It is worth noting that 'Little Mermaid' and 'Happenstance' originated as root-sports, as did 'New Dawn' and 'Mordelahanty'. Risley (1959) presented evidence of rose roots that do not get the full complement of chromosomes. "N.H. #5425 (Skinner’s Rambler x Yellow Pinocchio). A sterile triploid with ...
by Karl K
Fri Apr 15, 2022 12:05 pm
Forum: Rose Hybridizers Association Forum
Topic: A mini sporting to floribunda
Replies: 11
Views: 450

Re: A mini sporting to floribunda

There is an alternative mechanism that does not force us to imagine a mutation undoing another mutation. Ralph Moore (All About Miniature Roses, 1967), raised a useful idea regarding the nature of Miniature Roses: This brings up yet another often observed phenomenon known as witches'-broom. These dw...
by Karl K
Wed Apr 13, 2022 4:10 pm
Forum: Rose Hybridizers Association Forum
Topic: Time and Temperature
Replies: 9
Views: 547

Re: Time and Temperature

I've done more searching and found that my assumption about Rosa arvensis being pollinated in the evening/night is wrong. The authors below discussed a wide range of plants, and how they provide food for bees and other pollinators. The times listed are when the flowers are producing the most pollen....
by Karl K
Mon Apr 04, 2022 7:39 pm
Forum: Rose Hybridizers Association Forum
Topic: Rugosa×Hulthemia hybrids?
Replies: 20
Views: 960

Re: Rugosa×Hulthemia hybrids?

http://bulbnrose.x10.mx/Roses/breeding/Persica/PERSICA.HTML Harkness (1977) "Two seedlings of H. persica x R. rugosa alba also failed. Probably no two diploid species of roses are more dissimilar than H. persica and R. rugosa; at all events the seedlings from that cross try to make leaves from the s...
by Karl K
Mon Apr 04, 2022 5:54 pm
Forum: Rose Hybridizers Association Forum
Topic: Eva (Kordes) is tetraploid, coming from diploid seedparent?
Replies: 15
Views: 603

Re: Eva (Kordes) is tetraploid, coming from diploid seedparent?

I almost forgot ... well, I did until I was out watering the garden. Journal of Experimental Botany, Volume 62, Issue 10, June 2011, Pages 3587–3597, Polyploidization mechanisms: temperature environment can induce diploid gamete formation in Rosa sp. Yann Pécrix, Géraldine Rallo, Hélène Folzer, Mire...
by Karl K
Mon Apr 04, 2022 4:41 pm
Forum: Rose Hybridizers Association Forum
Topic: Eva (Kordes) is tetraploid, coming from diploid seedparent?
Replies: 15
Views: 603

Re: Eva (Kordes) is tetraploid, coming from diploid seedparent?

Unreduced gametes certainly occur, but the idea has sometimes been invoked too often. This came out in the genus Rubus where crosses between diploid raspberries and diploid blackberries result in triploids and the occasional tetraploid. No diploids at all. I read a paper (but can't find it now) wher...
by Karl K
Mon Apr 04, 2022 12:28 pm
Forum: Rose Hybridizers Association Forum
Topic: Has anyone tried compost activators?
Replies: 10
Views: 809

Re: Has anyone tried compost activators?

A small update: https://www.cambridge.org/core/journals/seed-science-research/article/abs/microbial-enhancement-of-seed-germination-in-rosa-corymbifera-laxa/7997D2C97BA89774E13F049632CFC1C4 Seed Science Research, 10(4), 489-494. (2000) Microbial enhancement of seed germination in  Rosa corymbifera  ...
by Karl K
Mon Apr 04, 2022 12:07 pm
Forum: Rose Hybridizers Association Forum
Topic: Time and Temperature
Replies: 9
Views: 547

Time and Temperature

Different species of a single genus can avoid cross-breeding by a variety of mechanisms. One of these is for the flowers to be receptive at different times of the day, even when they bloom during the same season. And "time of day" usually translates to "preferred temperature". For example, Gladiolus...
by Karl K
Tue Mar 15, 2022 1:24 pm
Forum: Rose Hybridizers Association Forum
Topic: Can Alba Maxima cross with diploids to create tetraploids?
Replies: 24
Views: 3987

Re: Can Alba Maxima cross with diploids to create tetraploids?

'Asta von Parpart' is sometimes very glaucous, sometimes not so much. It blooms early and late (November) in San Jose.
http://bulbnrose.x10.mx/Roses/Rose_Pict ... rpart.html
by Karl K
Mon Mar 14, 2022 1:29 pm
Forum: Rose Hybridizers Association Forum
Topic: more on climbers
Replies: 25
Views: 1912

Re: more on climbers

Hi Johannes You have an interesting rose that repeats and sounds like a nearly full hardy repeater. One of the interesting observations Margit makes in HMF is the Rosa beggeriana hybrid Polstjärnan (White Star of Finland) hip shape is significantly different from the globular hips of posted photos ...
by Karl K
Mon Mar 14, 2022 12:43 pm
Forum: Rose Hybridizers Association Forum
Topic: Bourbon Rose: The Prequel
Replies: 21
Views: 3611

Re: Bourbon Rose: The Prequel

Here's a note I found, misplaced, then found again. An Historical Relation of the Kingdom of Chile (1649/1703) Alonso de Ovalle The author merely included Roses in a list of plants that had been imported from Europe. The book was first published in 1649, then translated into English and published in...
by Karl K
Thu Mar 10, 2022 5:49 pm
Forum: Rose Hybridizers Association Forum
Topic: more on climbers
Replies: 25
Views: 1912

Re: more on climbers

I get lost with Beggeriana and its synonyms.
Atchison (1881) described R. anserinaefolia (Crepin, non Boiss.) as briar-scented. Does this agree with yours?
by Karl K
Mon Feb 21, 2022 2:10 pm
Forum: Rose Hybridizers Association Forum
Topic: Can Alba Maxima cross with diploids to create tetraploids?
Replies: 24
Views: 3987

Re: Can Alba Maxima cross with diploids to create tetraploids?

Forget about the septet business, the concept of septets is an historic artifact, part of a theory that is now obsolete and distracting. We have a detailed understanding now of how inheritance works in roses. One fact must be mentioned: there was no theory. Hurst presented mounds of data and his an...