I've currently been reading on the culture of the Apache, Tohono O'odham, and Raramuri, as well as other indigenous cultures in the Sonoran desert region. They would grow corn, beans, and grains, but I'm curious as to how they utilized water conservation to accomplish this.
Since you're in the literary area, as something of an aside please allow me to recommend Gary Paul Nabhan's "Gathering The Desert." It's beautifully written and illustrated, and goes deeply into the lifeways of the Tohono O'odham people. If you haven't read it already I'm certain you'll find it enjoyable and informative.