I recall having read or heard in an EA-related source that many (some?) tractors need  to periodically be connected (I guess to a GPS signal, but I don't remember) to function. Meaning that if somebody or something prevents this connection from happening enough time, it could be disastrous for food production, as many tractors would be unable to function even though they are in a perfectly good state. 

Does anybody know more about it? More details, the source, anything. It is very alarming!

[I am co-writing a report on AI and cybersecurity that will be used in an EU workshop that will help produce actions (eg. funding calls, etc) and I would like to mention this risk. The problem is that I have to hand it in tomorrow, so fast answers would be very appreciated! If you are reading this later, I'm also interested in late answers, they just won't help improve the report :-)]