Population life tables for the invasive fall armyworm, Spodoptera frugiperda fed on major oil crops planted in China

Abstract

The fall armyworm (FAW), Spodoptera frugiperda, is a newly invasive, widespread agricultural pest in China. Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy. Here, after FAWs were fed three important oil-bearing crops (oilseed rape, soybean and sunflower) planted in China and resultant population parameters were compared using the age-stage, two-sex life table method, survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower. Developmental duration of larvae on soybean was also the longest (23.3 days). The highest pupation rate was recorded on sunflower. The highest pupal mass (0.19 g) was attained on oilseed rape, significantly higher than on the other host plants; the lowest mass was on soybean (0.15 g). On soybean, oilseed rape and sunflower, respectively, the average generation period was 42.21, 39.10 and 40.44 d; the intrinsic rate of increase (r) was 0.0844, 0.1041 and 0.1134; the finite rate of increase (λ) was 1.0881, 1.1098 and 1.1202. While the most suitable host plant overall was sunflower, S. frugiperda completed development and increased its population on all three host plants. Thus, soybean, oilseed rape and sunflower were all suitable for FAW, and population monitoring and management of FAW in these crops should be increased.