I did some research on using triploids in breeding. If I understood what I read I learned that, 1) use the triploid as the pollen parent, 2) using triploid pollen on a diploid may result in either diploid or triploid offspring and 3) OP seedlings of a fertile triploid will either fall to diploid or raise to tetraploid levels (I have one OP seed of ‘Softee’ that I hope germinates).
‘Therese Bugnet’ is the only diploid that I have and was thinking about how I should use her this spring.
I have the triploids ‘Softee’ and my PMND-07-01 (‘Pink Meidiland’ x Rosa nitida ‘Defender’) and thought that I should use their pollen on ‘Therese Bugnet’. What do those who are familiar with TB think about using her as the pistillate parent in such a cross? Has anyone tried using triploid pollen on her? Thanks in advance.
I used Williams’ Double Yellow and John Davis on TB last year. I got the normal number of seeds per hip, but so far no germinations. Most of my other hardy diploids have been germinating enthusiastically over the past month. I wonder if TB is just slow.
I only did the two crosses. I recall missing just one normal size hip, but who knows how that happened. So I would say most took. Next year I’m thinking of using Carefree Celebration if the bloom times coincide.
TJ is relatively infertile but the good thing is that it produces pollen in abundance and it male fertile. So it should just be a matter of machine gunning a diploid relative to death, lol.
I have Therese Bugnet X Topaz Jewel seed germinating right now and some seedlings under lights. I made the cross on a whim because TB was ready for pollen and TJ was the most interesting rose I had pollen available from at that point.
I didn’t really expect the pollination’s to take as TB has been fussy for me and TJ has failed to pollinate any of the other roses I’ve tried it with. But all the pollinations from that cross took and I had a god crop of seed.
I’ll post some pics if anything interesting comes from it.
I tried for years with pure rugosa’s and it’s own pollen and got nothing but hybrid rugosa’s like ‘Sarah Van Fleet’ and ‘Topaz Jewel’ have produced masses of seed.
Perhaps it prefers a little modern blood in the mix?
That’s interesting, I may have to try TB again. I tried Magseed pollen I got from Paul B on it and it didn’t take. But last year it rained just about everyday and I had really poor hip and seed set on most of my crosses.
You might try Golden Unicorn and Dornroschen as bridges for Therese Bugnet based on the blanda ancestry of the former and the acicularis ancestry of the latter.
Watch for rust on Golden Unicorn if it’s an issue where you are. It rusted HORRIBLY here all last year and on the foliage it has currently. Very disappointing. It’s right up there with Wandrin’ Wind for rust here.
Thanks to David I have some Nyveldt’s White seeds in the fridge. Hopefully there will be a few repeat bloomers among them. They might be easier to work with using triploids than TB…it sounds like she’s a bit finicky.
‘Therese Bugnet’ definitely works well as a pollen parent, but only occasionally will it form seeds, and in my experience so far, it prefers pollen from other diploids.
Seedlings obtained using ‘Therese Bugnet’ in the past two years have been outstanding, with exceptional vigor, health and gorgeous Fall foliage.
“I tried for years with pure rugosa’s and it’s own pollen and got nothing”
I should have been a little clearer in the above statement. I got nothing from selfing TB, but its pollen has been perfectly fertile in other crosses.
I do think Therese Bugnet is well worth breeding, it’s just a mater of finding the right combination. And I have to agree with ‘paul b’ about the vigor, health, and particularly the fall colour of TB seedlings. The only negative I’ve found is that a lot of the seedlings have flowers that ball in the rain.
