Status of Spodoptera frugiperda (Lepidoptera: Noctuidae) as a Pest of Maize Based on the Relationship Between Infestation Area and Rainfall in West Sumatra, Indonesia

¹ Departement of Plant Protection, Universitas Andalas. Padang, Indonesia
² Departement of Agronomy, Universitas Andalas, Padang, Indonesia

^* Corresponding author: novrinelly@agr.unand.ac.id

Abstract

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), commonly known as the Fall Armyworm (FAW), is an invasive pest that causes significant damage to maize crops across tropical regions. This study aimed to examine the status of FAW as a maize pest in West Sumatra, Indonesia, focusing on the relationship between infestation area and rainfall. Monthly rainfall data were obtained from the Meteorology, Climatology, and Geophysics Agency of Indonesia (BMKG). Data on maize damage caused by FAW were collected from the Provincial Agriculture Service of West Sumatra, while population data were acquired through field surveys in major maize production areas. The data were analysed using correlation approaches to determine the relationship between FAW infestation intensity and monthly rainfall levels. The results revealed that FAW infestations occurred in almost all observation sites, with varying levels of damage; however, no significant correlation was found between rainfall and infestation area. This finding indicates that climatic factors, particularly rainfall, are not the main determinants of FAW outbreak dynamics in West Sumatra. Other factors, such as host plant availability, cropping patterns, and pest management practices, will likely play a more decisive role in influencing infestation intensity. These results provide important insights into the current status of FAW in West Sumatra and serve as a foundation for developing more effective and sustainable control strategies that account for complex agronomic and ecological factors.