In my case it's with the hard push to Hybrids, which is a major risk for the stability of the world's food supply (due to the strong mono culture, it's relatively easy for a willing player to first stock up on food, and then deliver pests for all major food hybrids that are only as effective because they are hybrids and not a healthy pool of genetic diversity. Also, if the hybrid seeds producing facilities were to be targeted, at the right time, it might not be possible to coordinate sufficient seeding of the available seeds, which the farmers might not even know how to plant/grow, as the non-hybrids are rather different from the hybrids, as far as optimum growing parameters go.

The primary issue with Monsanto specifically would then be that they actively try to prevent farmers from using non-hybrid seeds. Also, one would be surprised how well grains grow without pesticides, if the land is properly cared for. There was a time before pesticides were as widely available, and they did not have the time to weed the whole field by hand ;)