There are existing prototypes of laser systems for killing fast moving insects such as mosquitos. Imagine a device on a fence pole covering the surrounding acre.

There are plenty of slow moving pests, weeds and the like as well.

Or we could eat less fresh fruit, buy more fruit for baking and already canned fruit.

Where do you think that canned and baking fruit comes from? It's grown just the same.

Presumably, canned fruit could involve less organic waste as the canner can use ugly fruit that consumers may reject for long enough that it spoils.

I don't know enough to guess whether this is more energy 'efficient', given that we need glass or metal containers, in this case.

Yes, but there's probably less loss & spoilage in the supply chain for canned/frozen/dried/etc.

Same pest/weed control, though, and that's what we were talking about.