Effects of three artificial diets on development and reproduction of the fall armyworm Spodoptera frugiperda (J E. Smith).
Fall armyworm Spodoptera frugiperda (J. E. Smith) is an important agricultural pest invaded China in 2019, it is important to screen out the suitable artificial diets (AD) for its mass-rearing in laboratory. In this paper, the effects of three candidate artificial diets on the development, fecundity and population growth potential of S. frugiperda were studied by establishing the life table of experimental populations, and those reared on maize leaves were used as the control. The results showed that the three artificial diets had significant differences in the rearing effect of S. frugiperda. Among the three candidate artificial diets, AD-II was the best one. Although the larva-pupa developmental time (23.63 d for female individuals) of AD-II population was slightly longer than the control (20.98 d), biological parameters such as the immature survival rate (88.00%), female pupa weight (243.90 mg), male pupa weight (251.60 mg), and fecundity (845.90 eggs/♀) of AD-II population were superior to the control. Life table parameters such as net reproductive rate (R0, 346.29), intrinsic rate of increase (rm, 0.1859) and finite rate of increase (λ, 1.2043) of AD-II population were also higher than the control. Though S. frugiperda could complete its generation development when reared on AD-I, but the larva-pupa development time (41.56 d for female individuals) was prolonged significantly, the immature survival rate (36.00%) was quite low, and only 25.00% females could lay eggs, which made it difficult to meet the requirements for mass rearing of S. frugiperda. S. frugiperda those reared on AD-III could only grow to the 5th instar larvae, and could not complete its generation development. In conclusion, AD-II is a suitable artificial diet for mass-rearing of S. frugiperda.