I wonder how weeds and pests will evolve to avoid this technology. Will we end up with laser resistant plants?
This has already happened in history for weeds which came under artificial selective pressure due to practices of separating seeds, etc. The fascinating thing is that some of these weeds took on so many of the desirable properties of the primary crop that they became crops in their own right. Rye and oats originally being mimicks of wheat for example: https://en.wikipedia.org/wiki/Vavilovian_mimicry
The best strategy against such a source of massive trauma is probably not to be seen.
It is entirely possible that the robots will remember positions of individual crops and kill anything that grows outside the grid.
It is even possible that the robots will be capable of seeing individual cells on the plant and distinguish the species by morphology of the stalk.
So I think it's crucial here that the goals are external, and it's just natural selection if the goal is merely "Survive and reproduce" and the selecting factors happen to be man-made.
Weeds that evolve to hide from an AI weed zapper thus aren't artificial selection. Unless there's some comic book bad guy who decides to engineer such a thing.
A crucial difference in outcome here is that Mother Nature doesn't give a shit. Where there's a natural equilibrium, Ma doesn't ensure neither side wins. The wolves could become perfect predators, kill all their prey and then starve to death wiping out both groups. Mother Nature doesn't give a shit. But because we have an actual goal, outcomes that defy our goal are unacceptable and we'll tweak the selection process. That's what happened with dog breeds where the "preferred" type characteristics were so unhealthy that they're basically a death sentence.