Use of food attractants to monitor and forecast Spodoptera frugiperda (J. E. Smith) seasonal abundance in southern China

The fall armyworm [FAW, Spodoptera frugiperda (J. E. Smith)] is an important invasive pest of maize crops in Africa, Asia and the Middle East. To enable timely and effective pest management, accurate monitoring and forecasting of S. frugiperda populations is essential. In this study, we used food attractants to assess seasonal abundance of S. frugiperda in southern Yunnan (China) and determined adult age based upon ovarian development or testes size. During 2020–2021, the seasonal abundance of trapping S. frugiperda males with food attractants and sex pheromones were approximately the same at two field sites. Both trapping methods yielded S. frugiperda males of different ages—with an identical age structure for both trap types. The proportion of females trapped with food attractants was about 80%, which was significantly higher than that of males. S. frugiperda populations at two field sites were composed of immigrants that either originated in central Yunnan or in eastern Myanmar. Based upon field-level recordings of adult reproductive state, models reliably anticipated S. frugiperda fecundity dynamics. Next, drawing upon meteorological data and FAW adult age, migration trajectories were established for S. frugiperda immigrant populations. Overall, these novel (food-based) monitoring and forecasting tools can improve integrated pest management of S. frugiperda in China and abroad.