I’ve always assumed that some triploid roses are fertile and have used plenty of triploids in my breeding program. However, I just read a paper about apple breeding with triploids that make me wonder whether I’m wrong about this.
“All tested pedigrees from literature that listed triploids as parents of diploids were deemed false…These results together suggest that historic triploids are mostly or solely the product of diploid parentage and that triploidy has been a dead end…”
No argument. Mary Wallace ( [ Rosa luciae Franch. & Rochebr. × Hybrid Tea]) triploid crossed with several diploid wichuranas and Teas created Golden Glow, which created the known fertile triploid minis: Anita Charles and Golden Angel. It resulted in MANY other larger and mini roses, some of which could easily also be triploids but their ploidies aren’t listed. Golden Angel is a fertile triploid. When crossed with the tetraploid, Orangeade, it resulted in the fertile triploid Torch of Liberty. I crossed Torch of Liberty with Basye’s Legacy, a known tetraploid, and raised the triploid, Lynnie, which is about as fertile as they come.
Jim Sproul’s L56-1 hasn’t been tested, but it breeds as if it’s a fertile triploid. It accepts pollen from species very easily and is the only rose to easily cross with R. Minutifolia. Selfs of its first generation hybrids show a good deal of the species influence. I’ve also raised a number of seedlings using L56-1 and my Stellata mirifica hybrid, Puzzlement. They are all listed on HMF, most with photos.
I wish there were listed ploidies for all of New Dawn’s offspring. I’ve often wondered about Anytime’s ploidy.
How far they will go is anyone’s guess, but there are triploids which create more triploids. Exploring them is FUN!
I found the photos I wanted to include in my earlier post. The top foliage at 12 O’clock is L56-1; center is R. Minutifolia; 6 O’clock is L56Min2 (L56-1 X R. Minutifolia)’ 3 O’clock is one of the L56Min2 selfs; 9 O’clock is another L56Min2 self. Selfing appears to pull out more of the species influence.