admin answers:

I understand that the “application” of nanotechnology in agriculture is still mostly theoretical (hence my quoteation marks).
(and, of course, nanotech is *not* tiny robots, programmed to perform jobs … At least, not yet)

The possible applications include:
More sophisticated sensors to detect contaminants in agricultural products (a side-branch off Food Science or Pharmacology, I suppose).
Nanotech packaging to help prevent spoiling.
Indirect nanotech assistance in genetic or cell biological techniques used during selective breeding or genetic modification.

Current applications are generally “nanotech” ways to *use* agricultural products (like electrospinning silk or cellulose).

I have a little difficulty envisioning a pest-management application of current nanotech. The best I can come up with is nanotech-produced pesticides. Pharmacologists are working on nanotech-produced drugs (to improve efficiency of production), and I suppose the same principles could be applied to pesticides.