Good thread. Shadowrun does a lot better than most settings in the logistics of how things work. This is an interesting line of inquiry, because, as many here and elsewhere have said, he who controls the victuals has your balls in a vice. Everybody's gotta eat.
Some of the agritech is hinted at in the books or given a short once over. Its not terribly exciting and is of little use to shadowrunners, so they skip it mostly. But from what I understand, there are three major forces in agriculture in the Sixth World.
The corporations pushing heavily processed soy/tofu/krill/mycoprotein junk that is cheap to produce in as an industrial a way as possible.
More niche corps who still produce 'real food', aka corn, wheat, livestock for meat, etc. Stuff we're used to thinking of as food. Though we all eat the above as well.
Ecoconscious groups and corporations that produce 'real real food', organics and green-produced foodstuffs. Little or no pesticides, no GM crops, etc.
Most people in the civilized parts of the Sixth World eat mostly if not all of the first. Crap from Stuffer Shack. Chips and sauces, fried sticks of unidentifiable but tasty microwaved stuff. Jugs of totally artificial and brightly colored 'drink'. Crap. Filler calories with artificial flavorings and inserted nutritional content. Cheap to mass produce. They grow mycoprotein and krill in huge aquacultures and tanks. Soybeans are heavily genemodded for huge yields in industrial agricultural centers. The word 'farm' does not apply.
The second is more like the agribusiness of today. GM crops and livestock, industrial feed lots and tons of pesticides and so forth. Still recognizably food though, as opposed to raw mycoprotein. Dominated by the specialist agri-corps who sell to the upper class who can afford actual food.
The eco-conscious eater eats organic, non-GM foods and by nature probably has as little to do with the agri-corps as possible. There's a real movement in agriculture today to focus more on this. Smaller and family farms can survive if they go with a business model that integrates more biodiversity of crop types and diverse lineages of crops. Necessitates a much more labor intensive method of farming, as you can't design your farm around the huge combine harvesters and irrigation methods that current industrial farms use. Also translates into higher prices for the food you produce.
The poor eat the first, the rich the second, and the rich and green eat the last. The second and third overlap a bit depending on how organic the end product is. I believe the corps dominate the first and second, both to feed the masses and the upper class, and the third is people trying to break free of the cycle. I would assume the NAN has a lot more of the organic farming going on, but they still control huge amounts of farmland and have much lower populations than the UCAS and CAS. They must have plenty of large scale agriculture, most likely for export. The Azzies are supposed to dominate agriculture in North America, and possibly most of South America too.
I wanna know how Amazonians eat. The whole country, besides Metropole and Rio, are left to go back to jungle? What the hell do 50 million city dwellers eat?