CHAMPAIGN, Ill. — A new 30-minute documentary highlights three distinct stories about the University of Illinois Urbana-Champaign’s rich history of agricultural innovation and discovery, from its early beginnings to ongoing efforts of helping feed a growing global population to ways the university is nourishing its own campus community. “Rooted in Discovery: Agriculture at Illinois” premieres at noon Wednesday, July 8, on the Big Ten Network as part of the network’s Illinois Day.