Influence of larval nutrition on biological attributes and reproductive performance in Spodoptera frugiperda (Lepidoptera: Noctuidae) under laboratory condition

Abstract

An artificial diet and a rearing procedure for the polyphagous pest, Spodoptera frugiperda, were developed to facilitate its culturing under laboratory conditions [27 ± 1°C, 65 ± 5% relative humidity and a photoperiod of 14:10 (L:D) h] throughout the year. The efficiency of the diet was assessed through a comparative study with the natural host of the pest, maize. The biological, reproductive and population parameters of the pest on artificial diet were superior, especially the enhanced mean fecundity of 1796 per female which was more than that of the insect reared on its natural host. The meridic diet gave a higher mean pupal weight (0.217 g/pupa) than the natural diet (0.188 g/pupa). About 81.8% of neonates completed their developmental cycle on artificial diet and emerged as healthy adults, compared to only 57.5% normal adult emergence on the natural diet. On observation, there were 3678 and 3551 eupyrene sperm bundles in the adults emerged from larvae reared on artificial diet and natural diet, respectively. The net reproductive rate () for adults reared on artificial diet was 945.26, it being 703.7 for adults reared on a natural diet. With a sex ratio of 0.55, the biotic potential of S. frugiperda reared on artificial diet was 5.104 × 1028, which is more than that of natural diet (5.740 × 1026). The fertility life table constructed in the present study can play a significant role in predicting population dynamics, which will further help in developing an effective integrated pest management and the developed meridic diet with rearing procedure will be helpful in insecticide resistance monitoring programmes for this folivorous pest.