AKWindWatcher Not a disease expert but that looks like stem rot to me. There are many possible causes. Poor draining soil, bacterial infection, viral disease.... I'd cut to below the open part and see how far the damage goes. You might be able to still save it.
AKWindWatcher Caz-65 - We don't have those here so I've never seen their damage in person. If you trim the stem and find the culprit please report back. I would be interested to know either way.
katyaker Can anyone tell me what causes this blackening of the growing tip? I paid $31 for this tuber. Very disappointed with this supplier!
blown_dry katyaker The tuber and most of the growth look fine. I don't know what else was going on with the supplier, but this tuber seems raring to go. Trim it well below the spot that is bad and discard the problem bit and I doubt you will see the problem repeat.
Teddahlia I believe in the UK they call this "black leg". Cut it below the rot and probably will be ok after awhile. Some tubers that sprout in storage get this but when removed they grow very well. The sellers used to remove the sprouts before shipping but nowadays more people want them to take cutting. If the sprout had been removed(or just cut back) the tuber would have looked just fine.
