Hello to all!
It’s about the selection process based on leaf anomalies in a very early stage, few weeks after germination, which has bothered me since the beginning of breeding and makes me think about it anew every year.
Krüssmann, G., (1981), The Complete Book of Roses, stated very clearly that seedlings which have misshappen leaves should be pulled up for they never produce good flowers.
I have always followed this advice very carefully. Nevertheless, I would be interested to know how strictly you handle this matter. Thank you in advance for your comments and insights into your practice.
For a clear picture I have attached a few sample pictures:
I see a lot of weird stuff in the first few months that doesn’t seem to always follow into adulthood. I’m currently watching two crosses where one of the sepals has turned into a full pinnate leaf. I highly doubt it will recur.
Roseus, don’t worry–those leaves in your photos are not malformed in any way. They are simply at an intermediate developmental stage between undivided and compound. Whatever Gerd Krüssmann was referring to is something else, presumably something that would be evident once the seedling is producing more fully formed compound leaves, like unusually narrow leaflets. Also, it isn’t possible to prove such an assertion absolutely without seeing every seedling that ever existed. I would never say never, even if Krüssmann observed a genuine tendency for seedlings with malformed leaves to produce poor flowers. If you are risk averse or short on space you could cull them proactively, I suppose, but I would usually be too curious to do that.
Thank you both for your efforts and support! Unfortunately, like many of us, I too have to cope with limited space and am therefore forced to prioritise in my selection. I have also noticed time and again that the intermediate stage shown between undivided and compound development is occasionally repeated in such seedlings, also in later stages, which has reinforced my fear that it could be a disorder after all. Krüssmann’s reference proved this idea to be correct. In future, I will handle the matter a little more generously, as far as possible for me, and observe developments for longer.
I have never seen that in my seedlings, and am very surprised that you would have such a different result. If it happens again, would you be willing to share photos at a later stage?
Yes, of course, I will be happy to do so!
I had honestly never heard of shape of first leaves affecting the final result.
I used to get excited about orange and yellow leaves. Though such was clearly for want of chlorophyl, I too often hoped with futility for a chimera that might reveal itself with some green striping. I never had any such luck, and once the cotyledons were drained, the seedlings would expire.
(Of course, I still plant floaters… Probably due to working with some rugosas once.)