Search found 383 matches

by Larry Davis
Thu Dec 27, 2018 7:37 pm
Forum: Rose Hybridizers Association Forum
Topic: Video tour of FIVI3 seedlings
Replies: 7
Views: 130

Re: Video tour of FIVI3 seedlings

Impressive contrasts. What was the coldest night last winter? If those all grew back from roots, they have really impressive vigor.
by Larry Davis
Tue Dec 25, 2018 6:26 pm
Forum: Rose Hybridizers Association Forum
Topic: Rebloom
Replies: 23
Views: 782

Re: Rebloom

Points well taken. Longevity is also very temperature dependent among roses that last more than 1 day, in my experience. This is a characteristic that the knockout roses have, perhaps in excess. In our climate Rainbow KO will hold petals until they turn green and brown making some preddy ragged look...
by Larry Davis
Sat Dec 22, 2018 9:11 pm
Forum: Rose Hybridizers Association Forum
Topic: Flower bud differentation and growing in rosehip.
Replies: 14
Views: 358

Re: Flower bud differentation and growing in rosehip.

Karl, my error in speed reading. The authors used R wich and F & P which they simply call R hybrida with no comment on whence it may derive. I presume they used R wich as a readily available OF rose and F & P as a OF parental type for Little White Pet. I conflated the two observations but have no cl...
by Larry Davis
Wed Dec 19, 2018 9:15 pm
Forum: Rose Hybridizers Association Forum
Topic: Flower bud differentation and growing in rosehip.
Replies: 14
Views: 358

Re: Flower bud differentation and growing in rosehip.

Thank you David. There is a nice 2012 article that cites Roberts et al, and it's a free PMC article. I found it from it citing the abstract you linked. I think I read it previously but totally forgot. They compared CF sport Little White Pet with its R wichurana hybrid parent that is OF. Varied doses...
by Larry Davis
Tue Dec 18, 2018 11:06 pm
Forum: Rose Hybridizers Association Forum
Topic: Flower bud differentation and growing in rosehip.
Replies: 14
Views: 358

Re: Flower bud differentation and growing in rosehip.

I tried searching for flower induction in rosaceae. Lots on strawberry, some on blackberry and raspberry, little on once-flowering roses. Someone living in coastal Cal could give us the answer. Does foetida bloom in S.D., San Jose, S.F.? S.F. sure isn't hot in summer or cold in winter but it might g...
by Larry Davis
Tue Dec 18, 2018 11:02 pm
Forum: Rose Hybridizers Association Forum
Topic: Three-year screening for cold hardiness of garden roses
Replies: 5
Views: 227

Re: Three-year screening for cold hardiness of garden roses

My point was just that you could cool things at a rate emulating what happens outside. I know that there are times when it falls 50 F in 2 hr but mostly it is a cold clear night where the temp drops about 30 F from where it starts, then the next day rises partway up and drops a step further. so I wa...
by Larry Davis
Mon Dec 17, 2018 10:28 pm
Forum: Rose Hybridizers Association Forum
Topic: Flower bud differentation and growing in rosehip.
Replies: 14
Views: 358

Re: Flower bud differentation and growing in rosehip.

If I'm not mistaken there have been studies on the timing of when flower buds are formed in a number of rosaceae, and in fact for some it is in winter, not in summer. That's why you have to have a winter chill to get flowers on some fruits. Strawberries do it in late summer/fall except ever-bearing ...
by Larry Davis
Mon Dec 17, 2018 9:18 pm
Forum: Rose Hybridizers Association Forum
Topic: Three-year screening for cold hardiness of garden roses
Replies: 5
Views: 227

Re: Three-year screening for cold hardiness of garden roses

The actual hardiness testing described in the paper is rather elaborate and I think Donald has the right idea. But somehow you have to control the rate of freezing after storing the stems in a refrigerator for a couple weeks. I fairly confident that refrigerator acclimation is abslutely essential, a...
by Larry Davis
Mon Dec 17, 2018 8:52 pm
Forum: Rose Hybridizers Association Forum
Topic: Three-year screening for cold hardiness of garden roses
Replies: 5
Views: 227

Re: Three-year screening for cold hardiness of garden roses

Thank you Henry. I could not access the first article in Sci Hort from home. But I was referred to a similar article by Science Direct, and it is available without paying access fees. It focuses on 4 roses representing 4 hardiness zones, out of the 16 screened. Journal of Plant Physiology Volume 232...
by Larry Davis
Fri Dec 07, 2018 6:44 pm
Forum: Rose Hybridizers Association Forum
Topic: HUMAN AND ANIMAL HEALTH Some Hematological and Non-Specific Immune Responses of Rosehip (Rosa canina) - Fed Russian Stu
Replies: 3
Views: 168

Re: HUMAN AND ANIMAL HEALTH Some Hematological and Non-Specific Immune Responses of Rosehip (Rosa canina) - Fed Russian

Nyblom and associates in Scandanavia did a lot with trying to commercialize various caninae. There are also papers from Turkey, mainly in Acta Horticulturae I think. (That's a series of books publishing papers from various European meetings.)
by Larry Davis
Fri Dec 07, 2018 6:40 pm
Forum: Rose Hybridizers Association Forum
Topic: Rebloom
Replies: 23
Views: 782

Re: Rebloom

Occasional rebloom may well be buds that remained dormant in the first flush. Up the street there is an enormous, unpruned Dr. Huey which has occasional rebloom in mid to late summer in some years. I investigated and it appears to be later shoots are coming from further down the main canes that the ...
by Larry Davis
Mon Dec 03, 2018 10:41 pm
Forum: Rose Hybridizers Association Forum
Topic: Source of data on hip production by cultivar.
Replies: 6
Views: 334

Re: Source of data on hip production by cultivar.

I think not. Asaystematic review of germination studies (which I did and posted on the RHA site) identifies lots of plants that produce enough hips to get scored by someone somewhere. AT Help-Me-Find roses search you can look up the purported progeny of any rose listed there. That of course only ind...
by Larry Davis
Sun Dec 02, 2018 2:56 pm
Forum: Rose Hybridizers Association Forum
Topic: RrGT1, a key gene associated with anthocyanin biosynthesis, was isolated from Rosa rugosa and identified via overexpress
Replies: 5
Views: 199

Re: RrGT1, a key gene associated with anthocyanin biosynthesis, was isolated from Rosa rugosa and identified via overexp

I did a little detective work. The journal has changed names at least 3 times and is now Forest Ecosystems a Springer open access journal. Previous names, Forestry Studies, and Forest Science and Practice. The original article is available through Oriprobe information services for $31.95. I google s...
by Larry Davis
Sat Dec 01, 2018 8:28 pm
Forum: Rose Hybridizers Association Forum
Topic: Morphological Variation and Palynomorphology of Rosa laxa in Xinjiang, China
Replies: 2
Views: 125

Re: Morphological Variation and Palynomorphology of Rosa laxa in Xinjiang, China

Very interesting abstract. Is this a type of the R laxa Retzius that Griffith Buck used?
by Larry Davis
Sat Dec 01, 2018 8:25 pm
Forum: Rose Hybridizers Association Forum
Topic: Electron transport chain
Replies: 3
Views: 143

Re: Electron transport chain

Yes, a cartoon. I don't think the various complex I, II, III groups look much at all like the illustrations. For sure the ATPase is much more inscrutable. Even the best molecular dynamics simulations have a very hard time handling a protein with 50,000 atoms plus a few lipid molecules and a sprinkli...
by Larry Davis
Sat Dec 01, 2018 8:02 pm
Forum: Rose Hybridizers Association Forum
Topic: About #1100
Replies: 3
Views: 222

Re: About #1100

Good for you.I got three on one plant that was infected with RRD. Whether that had anything to do with it I have no idea. But no hips took on 2 other plants that were not infected. I was using pollen mostly of things like Carefree sunshine, Rainbow KO or whatever else blooms early. Of course I tried...
by Larry Davis
Fri Nov 30, 2018 10:17 am
Forum: Rose Hybridizers Association Forum
Topic: About #1100
Replies: 3
Views: 222

About #1100

Not to distract from David's achievements, I've moved this to a separate line. For Philipla. Unfortunately this rose took 5 years to bloom at all. I guess it needs a specific amount of accumulated biomass to feel like it. I made a bunch of cuttings this summer and will grow them out to see how many ...
by Larry Davis
Fri Nov 30, 2018 10:00 am
Forum: Rose Hybridizers Association Forum
Topic: RrGT1, a key gene associated with anthocyanin biosynthesis, was isolated from Rosa rugosa and identified via overexpress
Replies: 5
Views: 199

Re: RrGT1, a key gene associated with anthocyanin biosynthesis, was isolated from Rosa rugosa and identified via overexp

I think where they went astray was in accepting Zizhi as being "R rugosa" even while knowing that it is a hybrid. I'd say that's more a failure of the typical rose classification which bins things into groups that carry species names even when we know they' re hybrids. And secondarily that during tr...
by Larry Davis
Fri Nov 30, 2018 9:41 am
Forum: Rose Hybridizers Association Forum
Topic: Electron transport chain
Replies: 3
Views: 143

Re: Electron transport chain

Videos like that really recharge my battery. Good to see that someone is doing effective science communication. Now if they'd make one explaining how plants resist blackspot.....
by Larry Davis
Fri Nov 23, 2018 11:33 am
Forum: Rose Hybridizers Association Forum
Topic: Rising-Star-Honoree-David-Zlesak
Replies: 23
Views: 896

Re: Rising-Star-Honoree-David-Zlesak

Attempting to post a photo of #1100