Speculating about Stripes
James A. Sproul
(The background image is of a striped 'Lynn Anderson'
bloom)
A few weeks ago I made the most interesting discovery. As I was ripping
off petals of Lynn Anderson to prepare blooms for pollination, I noticed that one
of the bloom's I was ripping off had petals that were definitely all striped, white and pink!
Another interesting thing about this, was that the part of the plant that had the striped bloom on it was just adjacent to a plant of Scentimental.
Also, on examining the striped bloom, it was apparent that the form of the bloom
was very different. It did not have the exhibition form of Lynn Anderson, but rather the loose form of Scentimental. Additionally, the foliage was a
bit smaller than regular Lynn Anderson foliage.
This all got me to thinking. It was as if the branch was behaving in a way
that might be predicted of a cross between Lynn Anderson and Scentimental.
I have not been totally satisfied with the inheritance pattern of striped roses. It seems dominant, but with some crosses there seem to be other
factors that reduce the number of striped seedlings that would be predicted from a particular cross. I have read that many older striped roses were
thought to be the result of somatic mutations, while others were thought to be virus induced.
Could it be that the striping in roses really is the effect of a virus that is primarily transmitted via pollen? Perhaps the "striping
virus" usually only transmits the striping characteristic to the seedling embryo, and only
very rarely breeches through the seed contained in the hip to "infect"
the mother plant. There are certainly mammal models of viruses that transform
animal cells so that the entire virus genome becomes incorporated into the animal's DNA. It may be then that the virus moves only very poorly
through the mother plant so that what appears to be a spontaneous mutation in a branch exhibiting striped roses on a non-striped variety, is really a very
rare infection by a "striping virus".
I did attempt to pollinate the striped bloom. If any seeds result, I will of course plant them to see whether the striping is transmitted. If the
hip fails, I will try to graft all of the buds on the stem of the striped bloom.
Maybe it is just a fluke, but the coincidence of Scentimental being right next to where this "spontaneous mutation" developed, and the loose
form of the striped bloom, which was much more characteristic of Scentimental than
Lynn Anderson, led me to start speculating of the possible implications.
If striping in roses really is transmitted via virally transformed gametes it really doesn't matter. Striped roses are still very beautiful.
The circumstantial evidence is certainly thought provoking.