since a lot of food gets exported to the developed countries, would the customers in those countries still be able to trace down the origin of the product? That is, if I buy durian in America, would I be able to trace its origin and path atnleast until it reached America?

also,  I have to disagree about focusing on developing markets only, the World needs such tech everywhere. I dont see how expensive rfid tags can be used on 50 cent lettuce, so I do think that you should think big!