Should there be "the" in
The economy of the region relies on agriculture, which in turn depends on (the) weather.
Thanks!
It is not necessary. Both sentences are grammatically correct. They are also both semantically a little odd; they are very general sentences that express an idea that is very obvious. Perhaps you can explain the context more and we can figure out how to write the sentence more naturally.
I would use the article, just because without it, someone hearing the sentence spoken might confuse "weather" with "whether" and think the sentence was incomplete.
