native people in that area had a special relationship to corn for centuries before the arrival of the West. Short story is that corn was an early "science" target for genetically modified strains. A rough analogy to the conflict might be "vegetarian civilization considers cows sacred for centuries; new rulers decide cattle branding and breeding control are just commerce" .. something like that.. there is an emotional and cultural relationship to food, and long term residency in a place, that does not show up in commerce.
You can see evidence of this genetic experimentation with crops in Moray, a set of terraces built at different altitude levels created by the Inca culture in the Andes mountains [0]. It is believed that the Incas would acclimatize crops to the high elevations of the Andes mountains in these terraces.