what is it on my dendrobium ?

Hello,
Could you please tell me what is that green round bump on the cane of dendrobium. Is it some kind of desease? If yes, how can I cure it?
Thank you.

[Gin]

It is fine looks like the start of a new cane not anything to worry about .

[FairyInTheFlowers]

I think it might be a root, or like Gin said, a new growth, which should then be followed by new roots! Your dendro looks healthy, so there is definately nothing to worry about

Oh, I didn't know that cane grows on the existing cane, always thought it would come out beside the old one, from the roots.
Thank you guys.

[johnblagg]

lol your realy going to be upset when a whole new plant grows on the top of a old cane one day.....

I know, I have lots to learn. This is my first dendrobium and I don't even know what it's flowers look like. I bought it from discount shelf with flower stem cut off.
Now just trying not to kill it.
Thanks all for your help.