Mating-Induced Common and Sex-Specific Behavioral, Transcriptional Changes in the Moth Fall Armyworm (Spodoptera frugiperda, Noctuidae, Lepidoptera) in Laboratory

Abstract

The intermediate process between mating and postmating behavioral changes in insects is still poorly known. Here, we studied mating-induced common and sex-specific behavioral and transcriptional changes in both sexes of Spodoptera frugiperda and tested whether the transcriptional changes are linked to postmating behavioral changes in each sex. A behavioral study showed that mating caused a temporary suppression of female calling and male courting behavior, and females did not lay eggs until the next day after the first mating. The significant differences on daily fecundity under the presence of males or not, and the same or novel males, suggest that females may intentionally retain eggs to be fertilized by novel males or to be fertilized competitively by different males. RNA sequencing in females revealed that there are more reproduction related GO (gene ontology) terms and KEGG (Kyoto encyclopedia of genes and genomes) pathways (mainly related to egg and zygote development) enriched to upregulated DEGs (differentially expressed genes) than to downregulated DEGs at 0 and 24 h postmating. In males, however, mating induced DEGs did not enrich any reproduction related terms/pathways, which may be because male reproductive bioinformatics is relatively limited in moths. Mating also induced upregulation on soma maintenance (such as immune activity and stress reaction) related processes in females at 0, 6 and 24 h postmating. In males, mating also induced upregulation on soma maintenance related processes at 0 h postmating, but induced downregulation on these processes at 6 and 24 h postmating. In conclusion, this study demonstrated that mating induced sex-specific postmating behavioral and transcriptional changes in both sexes of S. frugiperda and suggested that the transcriptional changes are correlated with postmating physiological and behavioral changes in each sex.

Post-Mating Responses in Insects Induced by Seminal Fluid Proteins and Octopamine

“…In the PMR of ant queens, elevated expression of reproductive-related vitellogenin genes has been found, while defensin genes also show an increase followed by a return to normal levels within five days [104]. Similarly, in the PMR of Spodoptera frugiperda, aside from the downregulation of longevity-related genes, both female and male immune genes exhibit a similar pattern of upregulation followed by downregulation over time [105].…”

Receptivity and Remating Propensity in Female Spodoptera litura (Fabricius) after Mating with an Irradiated Male or Its F1 Male Progeny

“…Receptive females attract males by releasing pheromones during a characteristic 'calling' phase. Mating resulting in a temporary or long-term loss of sexual receptivity or reduced sexual attraction in many insects could be partly due to interruptions in pheromone production (pheromonostasis) and/or the absence of calling activity [26,27,73,74]. Mating has been reported to trigger a remarkable alteration in the reproductive behavior of both males and females in many insects, such as S. litura [45], E. kuehniella [75] and H. armigera [44] from Lepidoptera and D. melanogaster [42] from Diptera.…”

“…Mating has been reported to trigger a remarkable alteration in the reproductive behavior of both males and females in many insects, such as S. litura [45], E. kuehniella [75] and H. armigera [44] from Lepidoptera and D. melanogaster [42] from Diptera. Mated females exhibited less calling behavior and were resistant to remating attempts [28,73,76].…”

Blue Light Exposure Caused Large-Scale Transcriptional Changes in the Abdomen and Reduced the Reproductive Fitness of the Fall Armyworm Spodoptera frugiperda

“…However, empirical studies are required to determine how blue light causes damage to the thorax and abdomen. Recent studies on reproduction-and stress-induced (such as UV, thermal and chemical stress) responses in different tissues of different insect species based on RNA-seq and bioassay [37][38][39][40] have provided a rich resource to test the blue light stress response and possible mechanisms in different tissues of insects.…”