A lot of farms today are monocultures, meaning that only one crop is grown. This is apparently done because it's a lot less labor-intensive than growing and harvesting two or more crops in the same field, but monocultures are much more susceptible to disease.
Technological developments, however, may swing things in favor of polycultures. Robots tend to be good at repetitive, labor-intensive tasks such as harvesting (though some crops are certainly easier than others), so automated farms may be able to reap the benefits of polycultures without taking as big a hit in crop logistics.
I don't really know what I'm talking about here, but one day I hope to. For the moment, imagining the possibilities of automated farming is enough for me.