Survival of Fall Armyworm larvae and Yields of Field Corn After Artificial Infestations

Yields of field corn infested with 2nd instars of Spodoptera frugiperda (J. E. Smith) were not consistently reduced by infestations of up to 20 larvae/plant. Yield reductions following early- and middle-whorl infestations were associated with defoliation, whereas reductions in late-whorl and early-tassel infestations were associated with defoliation and damage to tassels, silks, and kernels. No larvae penetrated to the buds (apical meristems) of field corn plants. Survival of larvae declined during the 1st week postinfestation, then stabilized at 74%. Larval survival was lower when infestation occurred during the early-tassel stage vs. infestations occurring during earlier plant growth.