Relationship between fall armyworm and their natural biological control agents in the maize crop

This work had the objective of quantifying the losses in the maize hybrid BRS 3123 due to the attack of fall armyworm (Spodoptera frugiperda), in the absence or presence of its natural enemies. Fifteen days after the plant emergency, an artificial infestation (one egg mass per square meter) was accomplished. The larvae fed on the plant, without the interference of its natural enemies, by using an appropriated protection cage (initial protection for two days after infestation, until a maximum protection period of 16 days). The damage caused by the pest, determined through a visual scale from 0 (plants without damage) to 5 (dead plants), was on average, 4.01, 1.39, 1.09 and 0.93 for the pest protection period of 16, 6, 4 and 2 days, respectively. In the absence of the biological control agents, the attack of the pest caused losses of 47.27% in the dry matter production and losses of 54.49% in grain yield. The results evidenced the importance of natural enemies in the suppression of fall armyworm in maize crop.