Careful - overuse (such as with plants) might promote resistance in the malaria chain…

The malaria parasite Plasmodium has an organelle called the apicoplast which is biologically very similar to the chloroplast of plants (and is believed to share an evolutionary history with it). So it makes sense biologically that an anti-malarial drug could also work against plants if the apicoplast is affected.

https://en.wikipedia.org/wiki/Apicoplast

"Weeds" are a purely social construct, meaning only plants which humans don't like. These chemicals kill plants, not just weeds.

Some of the foremost pesticide manufacturers include Bayer, Merck, Colgate-Palmolive, SC Johnson, and Procter & Gamble.