A three-year evaluation of host crop use by the tobacco budworm [Heliothis virescens (F.)], was conducted from 2001 to 2003 in the central coastal plain of North Carolina. Weekly monitoring of commercial tobacco and non-Bt cotton fields revealed spatial and temporal patterns of host use, and showed that tobacco budworm may be produced in tobacco throughout the growing season. Small plot trials conducted in 2002 and 2003 demonstrated a strong oviposition preference of tobacco budworm for tobacco when located adjacent to plantings of alternate crop hosts. Moths collected in pheromone traps placed up to a quarter mile from primary sources of tobacco budworm production demonstrate sufficient short-range movement by adult insects to facilitate mating of individuals produced in distant cotton and tobacco fields. Results of this study indicate that flue-cured tobacco is an important host of H. virescens in North Carolina. The crop may also serve as a refuge for tobacco budworm from insecticide selection and play a critical role in insecticide resistance management in North Carolina.
