A further cross of interest. This time its a 2005 crossing from July, of Rosa rugosa f. alba x Golden Chersonese.
I have got a couple of plants as a F1 Population and they are remontant as I have noticed today: three bushes do have some flowers again, now in August 2010, - the first time they flowered in May 2010.
Features:
They are mildew resistant but not blackspot resistant.
They do have pink buds and pure white flowers.
The smell is a mixture of the rugosa rosy smell and the foetida like smell of the Rosa beggeriana!
They are very winter hardy, as the parents are.
Also of good drought resistance, as the parents are, I testet it several times as they grew in pots and got sometimes no water for long periods.
They (at least three bushes) are remontant. One flush in May, one in August so far.
I will add pictures soon, also on HMF, if possible.
I’m always surprised when disease resistance is lost in the F1. Let’s hope it can be recaptured in the F2.
As I’m sure you realize, remontancy in a species cross is a huge advantage, especially for cold hardy cultivars as you don’t have to rely on China influence.
The remontancy and winter hardiness where the reasons for me to do the crossing - and also the fact that Kruessmann writes that its difficult to breed with beggeriana as there is only one cultivar known: Polstjarnan (“Polar Star”).
So I saw it as a challenge … .
And I tried - and it worked - because of the conservative section crossing, I chose, I think.
And because of the fertility of Rosa rugosa - that is even good enough for fools!
So, as I think for the future: a crossing with my Rosa rugosa f. alba x Golden Chersonese plants could also lead to some fertile and salmon or light yellow flowering rose plants without China rose influence and at least a bit remontancy. …
By the way: It seems there is no disease resistancy lost, here the Rugosa alba is a cultivar that is not black spot resistant (there is a new paper out from Debener and I think Whitaker, where they found out that only their Rosa rugosa rubra was (recessively) resistant to black spot).
Do you mean the seedlings on the pictures above the last posting or the outcome of the crossing with Rosa ecae I did and wrote on yesterday?
For the first case: I will make a foto-comparing of the typical leafs of father mother and the F1. There is no doubt that they are no selfings. As i wrote in the first posting, they differ in smell, that is a mixture of the rugosa rosy smell and the foetida like smell of the Rosa beggeriana; also - what I didn’t mention - the autumn colour is a mixture of beggeriana (yellow to red with purplish tones in some years) and the fresh leafs smell a bit like rubiginosa (thats definitely not the case for the mother plant).
Hope this is right the answer on your question.
For the last case - well lets wait and see, a selfing of the F1 would be also ok, if the ecae pollen won’t hit.
But: normally selfings in dipoids (even in hybrids) are rarer than they are in polyploids.
Thats an important fact for the workings with them. …
