I've always wondered if it would be possible to incorporate carbon fixation schemes similar to those used by cactus into food plants (Grains might be difficult, but maybe different types of fruit and vegetables, citrus, which I understand is distantly related to cactus, for instance?).
Sure, growth rates would be slow, but the lack of need for irrigation and ability to utilize tracts of arid land might offset this.
I'm sure somebody at some point has looked into this. Any insight OP?
Fly-by comment: C4 is very similar to CAM, the scheme that cacti use. So the C4 rice project is essentially what you're thinking of, except that the reactions are separated spatially in C4 instead of temporally in CAM.
Sure, growth rates would be slow, but the lack of need for irrigation and ability to utilize tracts of arid land might offset this.
I'm sure somebody at some point has looked into this. Any insight OP?