Susceptibility of fall armyworm (Spodoptera frugiperda Smith) population to different insecticides at Dow AgroSciences, Santa Isabel, PR

Fall armyworm (FAW) (Spodoptera frugiperda Smith) is the most important pest of corn in Puerto Rico and insecticides are the major control options against the pest. Insecticide bioassay experiments were conducted to test susceptibility of field collected FAW population to key insecticides being used by Dow AgroSciences Research Station, Santa Isabel, and PR, to control the pest. Most of the insecticides tested showed more than 80% larval mortality 96 h after application. At 16 h after application, Radiant SC, Orthene 97, and Larvin 3.2 caused significantly higher (˃ 60%) FAW mortality compared to other treatments. Moreover, dose rate study of Tracer, Radiant, Orthene, and Larvin, that caused relatively fast kill of FAW larvae, showed that the current commercial dose rate is sufficient to control FAW.