Objective The study is carried out to explore the effect of mulberry leaf feeding on the growth and development of Spodoptera frugiperda, with an aim to provide a theoretical basis and reference for the potential damage of mulberry gardens caused by S. frugiperda.

Method The populations of S. frugiperda feeding on artificial diet and mulberry leaves were established by two-sex life tables, and the growth & development and reproductive indexes were measured, including the development duration, oviposition amount, pupal weight and pupation rate. And the population parameters were calculated with the two-sex life table software TWOSEX-MS Chart 2024, followed by ANOVA and graphing. Finally, TIMING-Mschart was used to predict the future 90 d population dynamics of S. frugiperda feeding on artificial diet and mulberry leaves.

Result The total developmental durations of S. frugiperda feeding on mulberry leaves and artificial diet were 44.18 (±0.93) and 32.30 (±0.26) d, the larval survival rates were 41.17 (±5.88)% and 55.56 (±12.73)%, the pupal weight were 174.4 (±34.2) and 225.9 (±23.7) mg per pupa, the oviposition amounts of single female moth were 499.58 (±278.67) and 877.40 (±440.79), and both of the pupation rate were 100%. The intrinsic rates of increase of S. frugiperda feeding on mulberry leaves and artificial diet were 0.10 (±0.01) and 0.14 (±0.01) per day, finite rates of increase were 1.11 (±0.01) and 1.16 (±0.01) per day, net reproduction rates were 128.57 (±36.37) and 250.64 (±77.14) eggs per single female moth, and mean generation times were 47.03 (±1.42) and 37.86 (±0.34) days, respectively.

Conclusion S. frugiperda feeding on mulberry leaves and artificial diet could complete the generation development, and compared with feeding on artificial diet, the growth and development rate of S. frugiperda feeding on mulberry leaves is slower, and the developmental uniformity, the survival rate, and oviposition amount are all lower. In conclusion, under natural conditions, when the population density is too large or the most suitable host plant is insufficient, it may pose a threat for S. frugiperda larvae to live on mulberry leaves.