The latest issue of CTA’s wonderful ICT Update is all about urban agriculture, and has a couple of examples of the application of GIS. I’ve always wondered whether urban areas act as “magnets” for PGR, people bringing their crops and varieties along when they migrate to the city and growing them in micro-environments, and/or as “winnowers” of the varieties available in the immediate vicinity, urban dwellers mostly focusing on the convenient and commercial. We even did an inconclusive study on sweet potato in Nairobi trying to look at this. Is genetic diversity much considered in urban agriculture circles?