Which organelle does the pesticide target?

It all depends on the pesticide which organelle is targeted. Organophosphates inhibit AChE. This is made by protein synthesis and excreted by the cell as a neurotransmitter. The organelle involved is the ribosome as it is not making AChE.

Aryloxyphenoxypropionate herbicides that inhibit acetyl coenzyme A (acetyl-CoA) which inhibits the beginning of the Krebs Cycle and so prevents the function of the mitochondria.

Miprophos-methyl, another pesticide is a mitotic tubuleinhibitor. It blocks cell division.