Dynamics of gut microflora across the life cycle ofSpodoptera frugiperdaand its effects on the feeding and growth of larvae

Abstract

BACKGROUND: Spodoptera frugiperda is an important invasive agricultural pest that causes huge economic losses worldwide. Gut microorganisms play a vital role in host feeding, digestion, nutrition, immunity, growth and insecticide resistance. Illumina high-throughput sequencing was used to study the gut microbial community dynamics across the life cycle (egg, 1st to 6th instar larvae, pupae, and male and female adults) of S. frugiperda fed on maize leaves. Furthermore, the gut microbial community and food intake of the 5th instar S. frugiperda larvae were studied after feeding them antibiotics.RESULTS: Enterobacteriaceae and Enterococcaceae dominated the gut during growth and feeding of the larvae. The relative abundance of Enterobacteriaceae was higher in the 4th and 6th instar larvae. With the increase in larval feeding, the relative abundance of Enterococcaceae gradually increased. In addition, principal coordinate analysis and linear discriminant effect size analysis confirmed differences in the structure of gut microbiota at different developmental stages. After antibiotic treatment, the relative abundance of Firmicutes, Proteobacteria and Fusobacteriota decreased. The relative abundance of Enterococcus and Klebsiella decreased significantly. Antibiotic treatment inhibited the gut flora of S. frugiperda, which decreased larval food intake and body weight gain, and prolonged the larval stage.CONCLUSION: The composition of the gut bacterial community plays an important role in the growth, development, and feeding of S. frugiperda. The results have a certain theoretical value for the development of bio-pesticides targeting intestinal flora.

Comparative analysis of Spodoptera frugiperda (J. E. Smith) (Lepidoptera, Noctuidae) corn and rice strains microbiota revealed minor changes across life cycle and strain endosymbiont association

“…FAW undergoes a complete metamorphosis in which a radical anatomical restructuring of the insect occurs, accompanied by functional and lifestyle changes ( Chen et al, 2016 ). These changes can severely impact the composition of the microbiota during the different stages of its biological cycle ( Paniagua et al, 2018 ; Li et al, 2022 ; Fu et al, 2023 ; Lü et al, 2023 ). This study investigated the composition of microbial communities throughout the biological cycle of FAW corn and rice strains using high-throughput sequencing.…”

“…Enterococcus is a genus of lactic acid bacteria with high metabolic and adaptive versatility ( Ramsey, Hartke & Huycke, 2014 ). This genus is commonly found in the gut of several Lepidoptera species ( Paniagua et al, 2018 ; Mason et al, 2020 ; Fu et al, 2023 ; Jeon et al, 2023 ; Han et al, 2023 ), and it has been reported as the dominant taxon in the gut Lepidoptera such as S. littoralis ( Chen et al, 2016 ), S. exigua ( Gao et al, 2019 ), Manduca sexta ( Brinkmann, Martens & Tebbe, 2008 ), Helicoverpa armigera ( Xiang et al, 2006 ), Lymantria dispar ( Broderick et al, 2004 ), and in S. frugiperda ( Higuita-Palacio et al, 2021 ; Li et al, 2022 ; Lü et al, 2023 ; Fu et al, 2023 ; Jeon et al, 2023 ; Han et al, 2023 ; Oliveira & Cônsoli, 2023 ). The persistence of Enterococcus throughout the life cycle of FAW suggests that this bacterium possesses efficient adaptive mechanisms that allow it to remain through different FAW developmental stages, and therefore, it might be vertically transmitted.…”

“…These studies have provided a single snapshot of the microbial species composition of the community ( Chen et al, 2016 ). Other studies have analyzed the microbiota in the corn strain during the FAW life cycle ( Fu et al, 2023 ; Li et al, 2022 ; Lü et al, 2023 ). Nevertheless, until now, none of these works has comprehensively investigated the FAW (CS and RS) strain microbiota throughout their life cycle.…”

Tetracycline inhibits tick host reproduction by modulating bacterial microbiota, gene expression and metabolism levels

“…In the laboratory, antibiotics are widely used in establishing sterile or microbiota‐altered host strains to explore the functions of symbiotic bacteria 22–28 . In ticks, antibiotic treatments have allowed us to clarify the contributions of symbiotic bacteria to tick development and survival.…”

“…In the laboratory, antibiotics are widely used in establishing sterile or microbiota-altered host strains to explore the functions of symbiotic bacteria. [22][23][24][25][26][27][28] In ticks, antibiotic treatments have allowed us to clarify the contributions of symbiotic bacteria to tick development and survival. For example, the ticks Amblyomma americanum, 24 Rhipicephalus haemaphysaloides, 25 Rhipicephalus sanguineus, 26 Rhipicephalus microplus 27 and H. longicornis 28 had reduced loads of Coxiella after antibiotic treatment, and the tick hosts showed blood-feeding and developmental abnormalities, confirming the essential role of Coxiella in these tick species.…”