I’ve noticed that in the backcross seedlings
from Rosa rugosa X glauca pollinated by Rosa rugosa
(just now germinating after second winter/stratification),
three out of nine seedlings are albinos.
I’ve noticed this high percentage of albinos in some
daylily crosses, but this is the first I’ve encountered
it in roses.
I don’t remember it being a problem with the F1, so I’m
guessing that maybe the rugosa is carrying the gene for
albinism. Or else it’s some form of incompatibility.
Tom, how does an albino seedling look?
I’ve never seen them–
I’ll try to get a picture tomorrow.
Until then here’s a link that gives you sort of an idea – just picture a rose seedling instead of cabbage seedling.
Tom, I’ve noticed that certain other “selfed” roses produce a larger number of albinos than when crossed with other roses. It would seem to be a recessive trait.
I have learned from the Worlds most famous Hybridizer’s book by Wilhelm Kordes II, that seedlings which do not turn green a few days after germination will eventually die.
I did not have many in my 36 years of hybridizing, but any Albino’s I have had, did not make it.
I’ve found that to be the case too that albinos usually die. There was one exception where the cotyledons were albino, but then green normal leaves came from the growing point. That was strange. Something kind of off the point that seems interesting to me is that many albino plants or plant parts actually do not lack the ability to make chlorophyll, but actually lack the ability to make particular carotenoids (chlorophyll accessory pigments). One role of carotenoids is to protect and slow down the rate of degredation of chlorophyll. Without it chlorophyll does not last as long. Chlorophyll is on chlorophyll binding proteins. If these proteins do not have chlorophyll on them they are also degraded and “recycled”. I am a teaching assistant for a plant physiology course this term and that is the mechanism behind the albino corn seedlings we germinated. We tried protein extractions from it and normal green corn to hopefully detect the lack of a band(or much fainter band) corresponding to chlorophyll binding protein. Supposedly Stelle de Oro daylily (diploid) when selfed gives 1/4 abino seedlings and contains a recessive for ablinism. Another side note too is lighting. We know that chlorophyll absorbs light in the blue and red spectrum. Plants generally reflect and do not use green light. There is also absorbance in other parts of the spectrum to varying degrees as well which are useful for photosynthesis. What absorbs these wavelengths is generally carotenoids and they pass along the energy /electrons to chlorophyll. Different plants have different carotenoids and concentrations of carotenoids and therefore use the light spectrum a little differently / effienciently for photosynthesis. My prof told me the researcher at Sylvania that designed gro lux bulbs was an african violet lover and used AF to optimize the spectrum for the bulbs. For other plants that may or may not be the most useful spectrum for maximized growth. Good thing roses are pretty versatile and grow well enough even under the inexpensive cool white bulbs.
Agree with David and George. I am sure that most hybridizers have had some of the albino seedlings, and probably tried to nurse them along. Some years ago we had one that we probably spent more time with it then all the rest for that season, but then it shriveled up and died. But it wasn’t all wasted, at least for the first time as it was a very good learning experience. Ever since then, we see one - out it goes. No hesitation!
Sometimes the cotyledons (the seed leaves) are albino, but the first true leaf that comes in is green. If the first leaves that come in are not green, the plant will not survive. Dump it.
Here’s a picture of those seedlings.
I’ve gotten occasional albinos before, and like everyone else has mentioned, they’ve always died. So, I don’t expect any of these to make it either.
But, I wonder though, if there’s a higher chance of getting variegated offspring from a rose that carries a gene for albinism. I’m imagining a variegated rugosa would be really popular. Or what about crossed to ‘Curiosity’, the variegated wichuraiana – then you might get a variegated Rosa kordesii. Wouldn’t that be cool!
So many plans, so little time.