For odour reduction (and comfort!) wear natural fibres. Synthetic materials are particularly bad at making the worst of a good sweat. Of the natural fibres, cotton is probably the worst, while in my experience hemp is excellent at reducing smells (even though it seems to stay damp longer).

Of course, different synthetic fibres perform differently, but as I don't often wear them, I haven't noticed which are better or worse, and I can't find any good references about the topic.