On the effects on agriculture, there's more to it than what it does to plants. Farm workers have been dying of kidney failure from working in hotter temperatures than the human body can adapt to. Even if the affected areas's plant life is still thriving, they're becoming harder to use as farmland.

It's been happening in all warm countries, but was first studied in Central and South America:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4974898/
Note that proper hydratation would help prevent the kidney failure effects, but for politically-charged reasons South American farm workers can't take breaks whenever they need, so "just drink more" isn't an immediate working solution.