Take tour of sugar producers, possibly, in river islands (10)
I believe the answer is:
dodecanese
'islands' is the definition.
(I have seen 'Greek islands' mean 'dodecanese' so perhaps 'islands' could also mean 'dodecanese')
'take tour of sugar producers possibly in river' is the wordplay.
I cannot really see how this works, but
'take' could be 'do' (eg taking or doing drugs) and 'do' is found in the answer.
'sugar' could be 'cane' (cane sugar is a kind of sugar) and 'cane' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for dodecanese that I've seen is " Greek islands".)