Search found 1766 matches

by Don
Tue Dec 04, 2018 9:59 pm
Forum: Rose Hybridizers Association Forum
Topic: Source of data on hip production by cultivar.
Replies: 6
Views: 159

Re: Source of data on hip production by cultivar.

Is your question directed at improving your yield of seeds for breeding purposes or some other reason like, say, aesthetics or vitamin c production or jam making? If it is to improve your yield of seeds then I would suggest that it doesn't matter much. If you can't get seeds from a plant as a mother...
by Don
Sat Dec 01, 2018 7:12 am
Forum: Rose Hybridizers Association Forum
Topic: Electron transport chain
Replies: 3
Views: 99

Re: Electron transport chain

I checked to see if they made a similar animation for the chloroplast but, alas, they did not. At first I thought it was some type of numerical simulation of structural data but I think what they did was to cleverly splice outtakes of some 3-d models and fill in the background with drawings, like a ...
by Don
Thu Nov 29, 2018 12:57 am
Forum: Rose Hybridizers Association Forum
Topic: Electron transport chain
Replies: 3
Views: 99

Electron transport chain

Mitochondria were first described two decades before the Civil War. It took another 120 years to work out the biochemistry of oxidative phosphorylation and electron transport chain coupling which was the state of knowledge when I was in college in mumble . By 1984 molecular biology grads were skippi...
by Don
Tue Nov 20, 2018 10:46 pm
Forum: Rose Hybridizers Association Forum
Topic: Rising-Star-Honoree-David-Zlesak
Replies: 20
Views: 411

Re: Rising-Star-Honoree-David-Zlesak

Kudos David!

I see in the announcement that you are collecting diplocarpon. How many strains are there in nature, and are you planning to market saltshakers filled with spores as a selection tool?
by Don
Sat Nov 17, 2018 4:05 pm
Forum: Rose Hybridizers Association Forum
Topic: New Zealand rose breeder
Replies: 1
Views: 102

Re: New Zealand rose breeder

Kudos to Rob Somerfield but this raises an interesting question. I checked just now and he is not and never has been on our membership rolls.

How are we failing breeders from other countries than the USA and Canada, and what can be done about it?
by Don
Sat Nov 17, 2018 4:04 pm
Forum: Rose Hybridizers Association Forum
Topic: Rosa sericea as a parent rose?
Replies: 14
Views: 656

Re: Rosa sericea as a parent rose?

I tend to regard morphological minutiae with regard to species as missing the forest for the trees. Most species are the result of reticulate evolution where you get a broad, sometimes continuous spectrum of morphology tied roughly to geography and geology. Moyesii is such a reticulate system where ...
by Don
Sat Nov 17, 2018 1:50 pm
Forum: Rose Hybridizers Association Forum
Topic: Rosa sericea as a parent rose?
Replies: 14
Views: 656

Re: Rosa sericea as a parent rose?

Turning your conjecture into reality begs two questions - is it possible to get a copy of any particular cultivar and, if you do, is it possible to hybridize with them successfully. I've addressed the latter question already - it is very difficult to get omiensis to hybridize. About ten years ago I ...
by Don
Thu Nov 15, 2018 8:31 pm
Forum: Rose Hybridizers Association Forum
Topic: Mapping a Novel Black Spot Resistance Locus in the Climbing Rose Brite EyesTM (‘RADbrite’)
Replies: 15
Views: 362

Re: Mapping a Novel Black Spot Resistance Locus in the Climbing Rose Brite EyesTM (‘RADbrite’)

Am I missing something? In that discussion Bill seems to let his statement stand that Bright Eyes is Radtee x Spotless Gold, and simply clarifies the ancestry of Radtee in his final post in response to Pat's request that he clarify the lineage of Bright Eyes.,
by Don
Wed Nov 14, 2018 2:40 am
Forum: Rose Hybridizers Association Forum
Topic: Mapping a Novel Black Spot Resistance Locus in the Climbing Rose Brite EyesTM (‘RADbrite’)
Replies: 15
Views: 362

Re: Mapping a Novel Black Spot Resistance Locus in the Climbing Rose Brite EyesTM (‘RADbrite’)

Wow. Double Wow. Forty years have passed since Peter Semeniuk released the Spotless series. Great to know that his efforts are yielding dividends. I remember at the time that the spotless roses were not well received commercially. Kudos to Bill Radler for carrying on with them. I wonder to what degr...
by Don
Fri Nov 09, 2018 10:48 pm
Forum: Rose Hybridizers Association Forum
Topic: Rosa sericea as a parent rose?
Replies: 14
Views: 656

Re: Rosa sericea as a parent rose?

I'll take a copy of Thor. >> The darned thing looks like it's decorated with razor wire. The Rogue Valley / Roses of Yesterday and Today (Stemmler) cultivar can give canes with the prickles running the full length of a cane uninterrupted. The two cultivars from Quarryhill are like the one in the pic...
by Don
Tue Nov 06, 2018 10:11 pm
Forum: Rose Hybridizers Association Forum
Topic: Rosa sericea as a parent rose?
Replies: 14
Views: 656

Re: Rosa sericea as a parent rose?

Good question. My first impulse is to say no but I don't really remember and there's no reason to guess. It's about 10:00 pm and raining but I hiked out and poked around the thicket to see if I could pick a piece of the cantabrigiensis f1. I got something but after looking at the bed map I realize i...
by Don
Mon Nov 05, 2018 4:30 pm
Forum: Rose Hybridizers Association Forum
Topic: Rosa sericea as a parent rose?
Replies: 14
Views: 656

Re: Rosa sericea as a parent rose?

I have a cantabrigiensis op that I grew from seeds copped from Kew Gardens. I'll be happy to send out pollen in the spring. For that matter I'll send seeds or pollen of any of my omiensis which were all winged to a degree. The most heavily winged, and most hardy, is the cultivar I got from Rogue Val...
by Don
Tue Oct 30, 2018 6:14 pm
Forum: Rose Hybridizers Association Forum
Topic: Rosa sericea as a parent rose?
Replies: 14
Views: 656

Re: Rosa sericea as a parent rose?

With one possible exception nothing ever came for me out of hundreds of pollinations using pollen from a dozen or so different omiensis and related cultivars onto everything in my stable. I did get seeds with embryos in very small numbers on rare occasions which either failed to germinate or died in...
by Don
Tue Oct 30, 2018 5:28 pm
Forum: Rose Hybridizers Association Forum
Topic: Compound Identification of Selected Rose Species and Cultivars: an Insight to Petal and Leaf Phenolic Profiles
Replies: 15
Views: 696

Re: Compound Identification of Selected Rose Species and Cultivars: an Insight to Petal and Leaf Phenolic Profiles

>> I never noticed a damask scent in 'Harriny'. Maybe that aspect of the perfume burned away in the San Jose heat. There are probably a couple of reasons for that besides that one. The biochemistry of terpenes has a lot of opportunity for variation based on things like temperature, sunlight and even...
by Don
Tue Oct 30, 2018 12:38 pm
Forum: Rose Hybridizers Association Forum
Topic: Compound Identification of Selected Rose Species and Cultivars: an Insight to Petal and Leaf Phenolic Profiles
Replies: 15
Views: 696

Re: Compound Identification of Selected Rose Species and Cultivars: an Insight to Petal and Leaf Phenolic Profiles

I'm interested in Lemon Delight for the prickles. I would like to see whether and how the hard and soft prickles express in combination. Mossing, being essentially up-regulation of and/or superposition of the glandular organs onto the prickles adds a third dimension. Composition of the essential oil...
by Don
Sun Oct 21, 2018 11:51 pm
Forum: Rose Hybridizers Association Forum
Topic: Harvested hips
Replies: 38
Views: 1675

Re: Harvested hips

Joe, I did avoid specifying which diseases I have seen on account of I have no idea except, sure, fungii are a significant factor but so are bacteria. Some embryos get coated in slime, some go pink like serratia marcescens, some get fur coats, some disintegrate into fluid. It's downright discouragin...
by Don
Sun Oct 21, 2018 10:15 pm
Forum: Rose Hybridizers Association Forum
Topic: Harvested hips
Replies: 38
Views: 1675

Re: Harvested hips

'Germination percentage' is a terrible metric when it is defined as the number of achenes from a hip that germinate. It ignores two not so obvious facts. Many achenes have no embryos. Often times most achenes have no embryos. Sometimes no achenes have embryos. The float/sink screening method whereby...
by Don
Sun Oct 21, 2018 10:07 am
Forum: Rose Hybridizers Association Forum
Topic: Harvested hips
Replies: 38
Views: 1675

Re: Harvested hips

I have found that soaking achenes in plain water for a couple of days - 'imbibing' - is enough to completely hydrate the embryos in all cases. As Larry points out, hydrostatic pressure is a powerful force but apparently not enough to split open achenes. The reason for this is that the achene forms a...
by Don
Tue Oct 16, 2018 11:36 pm
Forum: Rose Hybridizers Association Forum
Topic: Rainbow Roses
Replies: 10
Views: 612

Re: Rainbow Roses

This paper on rice de-domestication gives another case where suppressing a carbohydrate sink boosts yield - girdling without the trauma.

https://phys.org/news/2018-10-loss-micr ... -rice.html