Question on pollen form a female r. Setigera

General Discussion
1

Hi all

Can I use this pollen on other rose? I know the plant itself is female but what of the pollen.

thanks

paul e

2

Dear Paul,

Hi! I love R. setigera. It is very interesting to me in that it is a species with cryptic dioecy and the only rose that is dioecious (male and female plants). Even though it has male and female plants by casual observation one can’t easily tell the difference when the plants are in bloom (refers to the cryptic part). This allows the plant to have pollen eating insects visit both sexes and pollinate them! Tricky, eh? Well, from my reading some female plants can have a very small fraction of pollen that is viable and non-aborted. If I remember right when I looked at the pollen of the female plant at the U of MN arboretum collection it was all aborted and shriveled. For efficiency it would seem better to use a male plant that naturally has very fertile and viable pollen grains when using R. setigera as a male, but if you don’t have one trying your female is sure worth a try.

Please let us know your results! I haven’t came across any strong documented evidence, but I think that R. setigera may be the product of some introgression from Rubus (raspberries and blackberries). It is commonly called the blackberry rose. It trails wildly, blooms later than most roses, has foliage similar in some respects to blackberries, dioecy is present as in some Rubus… There are a lot of little clues that seem to add up to the possibility. It would be interesting if someone took the time and money to find molecular markers unique to Rubus and see if some are present in R. setigera.

Take care,

David

3

Hi David

Thanks for the information.

If the rose is a product of ether raspberries or blackberries would it be possible to recross with one or the other? I don’t have the room for such an experiment but the results would be interesting if it could be done.

thanks

paul e

4

David and all, do the male plants make no seed at all, or just small, non-viable seed? The reason I ask is that I have a plant that I purchased several years ago from Heirloom Roses as R. setigera “striped.” There was no description. Well, it is striped (white and very light pink, you have to be close to see it), but it is also semi-double. Its seeds come in all sizes, mostly small. I have never been able to germinate one. I did, however, find a seedling near the parent plant, which I have saved. It isn’t big enough to bloom yet. I have only tried the pollen once, and it didn’t work (on ‘Mutabilis’), but that doesn’t mean much. The plant shows no sign of being a bybrid. It’s stunning in bloom.