A few years back, a most bizarre bloom appeared on my Therese Bugnet rose bush. A double blush-pink flower that bloomed from an auxiliary bud. It had no stem and protruded directly from the stem/leaf axle. The flower was smaller and quite different from those of the Therese Bugnet mother plant. As you can see below, it’s nestled right in the leaf axle. This happened only once.
It should be a sport. Sports occur because the “genes took a walk”. They divided oddly and produced different growth. Some lines appear to be so unstable, they mutate continuously while others are sufficiently genetically stable they never do, or, at least, if they do, their mutations aren’t noticed. Weather conditions can sometimes cause oddities. I don’t think there is a definitive explanation to provide sufficient answers to your questions. All of Nature (us, included) reacts to the conditions it is exposed to. Flowers appearing directly from a growth bud isn’t common but it’s also not unheard of. If you’re lucky, that bud will produce a cane carrying that mutated flower, providing you the opportunity to isolate it and see if it’s something worth using and spreading around. It may, or may not. Time will tell. Good luck. I hope it gives you that and you’re able to grow it and evaluate it. Sports can be a lot of fun!
More commonly, a sport results in one morphological change, whereas this has both color and shape changes, but you hold all the cards to determine if this is rising from what you have established to be TB.
Is it genetic mutation or physiologically induced? I don’t know of toxins or diseases that would cause that…
Robert had a color sport from TB: ‘TBSPORT’ Rose 'TBSPORT' Rose
Yes, it is lovely, isn’t it? Quite dainty - almost like a carnation, lol. Unfortunately, no cane development and this peculiarity hasn’t occurred since or at least so far.
