Invasive Species Compendium

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Abstract Full Text

Comparison of the feeding and growth characteristics of larvae of the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), on corn and wheat.

Abstract

Aim: To assess the risk of damage and outbreak caused by the fall armyworm, Spodoptera frugiperda, shifted to wheat. Methods: The feeding and growth characteristics and population life table parameters of S. frugiperda on corn and wheat under 23°C in the laboratory were determined and compared by indoor breeding and survey statistics. Results: S. frugiperda could complete its life cycle on wheat, and the food intake and body weight of larvae after the 3rd instar fed on wheat were significantly higher than those fed on corn at the same time after treatment, but the food utilization efficiency, larval survival, larval duration, and egg hatching rate fed on wheat were significantly lower than those fed on corn. There were no significant differences in such indexes as the average pupal weight, pre-oviposition period, and number of eggs laid per female of S. frugiperda fed on corn and wheat. In addition, the comparison of life table parameters showed that there were no significant differences in the mean generation time (T), intrinsic rate of increase (rm), and finite rate of increase (λ) of S. frugiperda fed on corn and wheat, but the net reproductive rate (R0) of S. frugiperda fed on corn was 303.55±2.04, which was significantly higher than that fed on wheat. Conclusion: S. frugiperda fed on wheat grows and develops fast and can complete the life cycle. However, the food utilization efficiency and population reproductive ability of S. frugiperda fed on wheat are lower than those on corn, suggesting that S. frugiperda is more suitable for feeding on corn. There is a risk of shifting to damage wheat by S. frugiperda. But considering the source of the pest, natural temperature and other conditions, S. frugiperda is less likely to have an outbreak during damaging wheat. The results of this study provide basic data for clarifying the risk of S. frugiperda damage and outbreak on wheat and the scientific control of S. frugiperda.