Small interfering RNA molecules could be used as species-specific pesticides.

This would work on crops that are not genetically modified, by spraying on the RNA.

Getting them into the cells of the targeted species is a difficulty. An idea that occurs to me is to build them into a genetically modified version of a virus that targets that pest species.

The RNA molecule might randomly interfere with other genes in other species. However, the virus probably won't get into cells of most other species. With two keys that need to fit two locks, the chance of affecting other wildlife would be much less.

The idea is very interesting, but it is not without danger to the environment. It could also conceivably hurt humans — that is unlikely but needs to be tested.

I don't trust Monsanto to test this carefully, because its interest is to be careless.