The study evaluated heliothine larval survival on selected reproductive structures of conventional non-transgenic and VipCOT cotton cultivars. The plant structures included intact squares with bracts removed, bracts removed from squares, terminal leaves (first fully expanded), flower anthers, flower petals, and small bolls (2 to 3 d-old). Each structure was infested with 2-day-old heliothine larvae and allowed to feed for 96 h. Larval mortality was rated at 24, 48, 72, 96 h after infestation or until all insects on selected structures died.