Has anyone had luck getting healthy seedlings using ‘John Cabot’ in breeding?
Last winter I grew some seedlings from a cross using ‘John Cabot’ as a female parent, and they were weak, small, one appeared nutrient deficient in spite of all kinds of corrective measures being taken, and all of them died more or less quickly of seemingly genetic causes. Then last summer, I decided to try ‘John Cabot’ as a staminate parent with a very distantly related (to both it and the previous breeding partner) rose. The seedlings, however, have shown a very similar pattern of problems to the previous batch. One simply stopped growing when its first true leaf was still less than 1 mm long, then proceeded to die, and another appears to have been born entirely without the ability to produce true leaves (there is absolutely nothing going on between the cotyledons when viewed under magnification) and is also now dying almost a month after germination. I’m about ready to abandon using JC, even though it’s quite fertile (at least as a pollen parent) and the seeds have germinated well enough, but I am curious to know if someone has had better experiences with it first.
Stefan,
I got John Cabot only last spring (I think), and got only one hip (5 seeds) from 5 pollinations. No germinations yet. HMF doesn’t show any descendants. I did find one on the Web. See link below.
Peter
Link: www.home.no/rogersrosesider/trad95xjohncabot.html
I only get about 2 seeds per op hip from John Cabot so I’ve never considered using it for seed, although I do collect op seeds. I did use its pollen on the floribunda “Embers” several years ago & was able to get good germination & nice healthy plants from it with colors from yellowish to dark red. They all bloomed within 2 months of germination. Some of them even survived an uncharacteristically cold winter as first year seedlings. Alas the yellowish one didn’t. Don’t despair. In any population you’ll have distorted seedlings. I think your sample of crosses wasn’t big enough. Don’t give up. I think John Cabot could be a good rose to use on yellow roses to get warm colors since it already has yellow in its background.
On the other hand, there are other explorers which have a proven track record as seed parents.
Thanks! Then I may try again with different roses in the future; it must have been my bad luck. The first attempt used pollen from the miniature/miniflora ‘Shooting Star’, which I chose partly because it also shares ‘Goldilocks’ in its background and has a yellow/orange/red blend color. After eventually losing those seedlings, I thought I may have awakened some kind of lethal gene, so I tried John Cabot’s pollen on a damask with a different goal in mind. I was just surprised to see the very same problem in the seedlings and blamed JC for it. None of my attempts to use ‘John Cabot’ as a pistillate parent were successful this year, so I decided to avoid that in the future. I’ll try to think about other roses I might want to cross it with… maybe something that’s very fertile as a seed parent. Thank you for setting me straight!
We had one hip using John Cabot as a pollen parent. A few very small seeds with no germination as of yet, so as far as we are concerned not too viable. Will keep watching and hope for some germination. The seed parent is one of our seedlings.
My feeling about ‘John Cabot’ is that it has been neglected in a breeding program as a staminate parent. The pollen appears to be very viable. I don’t even think about it as a pistillate parent (just one of those intuitive judgments). Last year I used it with ‘Hansa’ and had good results. This year it is a priority to use with Rosa rugosa/acicularis tetraploid cultivars like ‘Carlos Dawn’ and ‘Lac La Nonne’. I think it should also be used with OGRs.