Level of damage caused by <i>Spodoptera frugiperda</i> J.E. Smith (Lepidoptera: Noctuidae) on corn plants with several intercropped plants

Abstract Spodoptera frugiperda is one of the major pests in corn and is known for its polyphagous nature. One factor influencing the population development of S. frugiperda in the field is crop planting patterns. Intercropping main crops with repellent plants can reduce pest infestations. The objective of this study was to determine the effect of three types of intercropping plants on the infestation of S. frugiperda in corn. The study used a Randomized Complete Block Design with 4 treatments (monoculture corn, corn + ginger, corn + basil, and corn + lemongrass), each replicated 5 times. The observed variables were the early infestation of S. frugiperda , the population of S. frugiperda egg groups and larvae, the percentage of plants attacked by S. frugiperda , and the intensity of S. frugiperda infestation. The research showed intercropping, especially corn + ginger treatment, significantly delayed and reduced S. frugiperda infestation compared to monoculture corn. The population larvae of S. frugiperda in monoculture corn and corn + ginger treatments showed significant differences (ranging from 0.02 to 0.11 individuals per plant). The observation of the percentage of plants affected by S. frugiperda in intercropping treatments indicated mild infestation (21.8 to 24%), whereas monoculture corn showed moderate infestation (35.6%).