ASHS abstracts for 2009 conference on line

I’m excited for the blackspot research I’ve been a part of this past year with colleagues to support Earth-Kind rose research. We have a talk submitted and accepted for this summers ASHS conference. You can see the abstract at: The 2009 ASHS Annual Conference: Evaluation of Landscape Roses From the Earth-Kind� Trials: Race-Specific Black Spot (<i>Diplocarpon rosae</i> Wolf) Resistance and Ploidy

Dr. Byrne has an abstract on evaluation of blackspot resistance in the field. The 2009 ASHS Annual Conference: Field Assessment of Black Spot Resistance In Roses Iin a Hot Humid Climate

The search feature doesn’t seem to be working yet to easily find all the rose research.



“Rosa wichurana ‘Basye’s Thornless showed no black spot development beyond an occasional infected leaf.”

I’ve seen this one and though it’s smooth, the rachis have prominent and vicious prickles. It has a tendency to tip root and come back from root cuttings very easily.

In certain climates I would guess it could become invasive and troublesome. After seeing it I decided not to take it on. It might be one of those worth keeping in a container permanently.

Here’s an additional rose abstract looking at a collection of rose cultivars in Romania.

Here’s another one by Dr. Byrne and a student looking at molecular markers in China roses and their relatives.

I’m confused about Robert’s quote referring to “R. wichurana Basye’s Thornless”. What rose are they talking about? My understanding is that ‘Basye’s Thornless’ aka ‘Commander Gillette’ is a R. carolina hybrid, and has nothing to do with R. wichurana. Can anyone clarify this for me please?

By the way, I also grow ‘Basye’s Blueberry’ and in my climate where 85% of all rose cultivars get modest to severe Blackspot, this is one of the very few that does not Blackspot at all when left to grow untreated for the disease. (IE: no fungicides) I have some F2 seedlings of ‘Basye’s Amphidiploid’ here as well and the biggest, most vigorous of the lot gets no Blackspot either. (It also happens to have blazing red and orange Fall foliage) I think Basye was definitely on the right track in using the native American species in his pursuit of Blackspot resistance.

I have one seedling from a 2000 cross of R. foliolosa X ‘Little Chief’ (of all things!) that has a very species-like growth habit and has been 100% Blackspot free here. David Zlesak tested it and determined it to be a diploid, and it is pollen fertile. I will be using it quite a bit this year in the hopes that it might contribute to superior immunity to Blackspot.

As an aside, it was interesting to note that of the four seedlings I got from the cross of R. foliolosa X ‘Little Chief’, one looks a lot like ‘Basye’s Purple’! It is smaller in habit, but has the same 5 petaled deep purple flowers that look very similar to ‘Basye’s Purple’. It seems that you can put a variety of pollen on R. foliolosa and get seedlings that look like ‘Basye’s Purple’. What an odd phenomenon. I will see if I can find a photo of it.


It would be great if one of your foliolosa x ‘Little Chief’ carries a gene for remontancy Paul. I couldn’t get foliolosa to flower in my climate.

I think this is the cultivar the article is referring to. (see link) As far as I know Basye was attempting to use it but I don’t have information that it originated with him.


Hi Paul,

Dr. Basye had a selection of wichuarana that was thornless. I am growing it now. I just got cuttings of it last spring from Kim Rupert. I believe he got it from Mr. Moore.


Hi Paul,

I’m confused too with the nomenclature for ‘Basye’s Thornless’. I have the tetraploid R. carolina hybrid and enjoy it. It is really hardy. ‘Basye’s Blueberry’ is surprsingly hardy here in zone 4. I suspect there are two out there with the same name of ‘Basye’s Thornless’. The BT that Dr. Byrne is talking about I suspect is straight R. wichurana. I just got a plant of a Basye’s Thornless wichurana from Mike Fitts last fall. Dr. Byrne has been using this diploid wichurana form to generate diploid populations and backcrosses with ‘Old Blush’. These populations are being used for molecular mapping studies and trait inheritance characterization. It sounds like ‘Old BLush’ is a carrier for thornlessness, although itself it isn’t.



Ahh, that would make sense. The way it was listed, it was unclear whether it was talking about a cultivar of R. wichurana or ‘Commander Gillette’. It should have been listed then as R. wichurana ‘Basye’s Thornless’ to avoid confusion.

R. wichurana is capable of breeding thornless seedlings, I believe. Ralph Moore’s “0-47-19” has occasionally given me near-thornless offspring. It is also giving me some of the most highly disease free seedlings of any of the parents I am using. It can be frustrating to work with though, as it often forms seeds by the bazillion and then when it comes to sowing them, you get zero germination of some crosses. In 2007 I made hundreds of pollinations with ‘Home Run’ on 0-47-19 and got thousands of seeds. Only one germinated and it died after struggling for three months.

This year I have thousands of seeds of 0-47-19 X ‘Hot Cocoa’ and I am greatly relieved to see many seedlings come up already. (However, I am bracing myself for loads of pink seedlings, and 3/4 or more will be once bloomers!)