in the past peach tree was cultivated, at least in europe, for everything else than its tasteful fruit because it was considered suspicious.
The sentence is not very well written -- I would say In the past, the peach tree was cultivated, at least in Europe, for everything other than its tasty fruit because it was considered suspicious. (Even that is not great, because it's not clear whether "it" refers to the tree or the fruit, but it's better than the original.)
It means: In the past, people (in Europe, and maybe elsewhere) grew peach trees, but not for the fruit. (Perhaps for the wood, or for shade, or something else.) They thought that the fruit might be dangerous to eat.