Genomic features of the fall armyworm (Spodoptera frugiperda) (J.E. Smith) yield insights into its defense system and flight capability

Abstract

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) is an agriculturally important insect pest and causes significant economic loss due to its resistance to insecticide and high dispersal ability (i.e. long‐distance flyer). We performed comparative genomics analysis based on the recently released chromosome‐scale genome of the FAW to investigate the genetic mechanisms of FAWs defense system and flight ability. The gene families encoding receptors for bitter or toxic substances and detoxification enzymes, such as cytochrome P450, carboxylesterase and glutathione‐S‐transferase, were expanded in FAW, enabling its ability to detect and detoxify many plant secondary compounds. The chromosomal locations of five detoxification‐related genes (i.e. ABC, CCE, GST, P450, and UGT) were analyzed, which revealed the density of these genes across the FAW genome. Several genes like Mio, Sik2, CRTC, and Lpin were positively selected in FAW, which were associated with energy metabolism, lipid metabolism, and/or muscle development, and thus possibly contributed to the high flight ability of FAW. We also analyzed the homologs to antimicrobial genes reported in the Drosophila genome, and identified 2 attacins, 6 cecropins, 3 gloverins, and 2 moricins in FAW. The findings of this study will broadly expand our knowledge on the biology of the devastating FAW, and contribute to the development of new pest management strategies for the control of major agricultural pests like FAW.

Differences in microbiome composition and transcriptome profiles between male and female Paederus fuscipes harbouring pederin‐producing bacteria

“…As previously described (Zhou et al, 2020), insect protein sequences of PGRPs were obtained from NCBI and used as a query after removing the redundant sequences through CD-HIT v4.6.1 (Fu et al, 2012). For homology prediction, proteins of the above PGRPs were mapped onto the transcriptomes using TBLASTN with an E-value cut-off of 1E-5 (Altschul et al, 1997).…”

Improved genome assembly provides new insights into the environmental adaptation of the American cockroach, Periplaneta americana

“…P. americana feeds on garbage and sewage and generally lives in moist and unsanitary areas, which results in abundant opportunities to be exposed to microbes and pathogens for P. americana (Chaurasia et al, 2016). Chemical pesticides have been widely used against pests which has led to the development of insecticide resistance of pests (Zhou et al, 2020). Positive selection provides evolutionary innovation in adapting to specific environments.…”

“…According to our previous research (Zhou et al, 2020), we used a consistent method to screen chemosensoria‐related genes (olfactory receptors [ORs], gustatory receptors [GRs], ionotropic glutamate receptors [IRs], odorant‐binding proteins [OBPs], chemosensory protein [CSP], and sensory neuron membrane protein [SNMP]), detoxification‐related genes (cytochrome P450s [P450s], glutathione transferases [GSTs], ATP‐binding cassette transporters [ABCs], carboxyl/choline esterases [CCEs], and UDP‐glycosyl‐transferases [UGTs]), and five antimicrobial peptides (AMPs) (attacin, cecropin, defensin, gloverin, and moricin). The redundant sequences of insect protein sequences (ORs, GRs, IRs, OBPs, CSPs, SNMPs, P450s, GSTs, ABCs, CCEs, UGTs, attacins, cecropins, defensins, gloverins, moricins) obtained from NCBI were deleted by cd‐hit (W. Li and Godzik, 2006).…”

BIOLOGY AND MORPHOMETRICS OF THE FALL ARMYWORM, Spodoptera frugiperda J. E. SMITH (LEPIDOPTERA: NOCTUIDAE) IN IBADAN, SOUTHWEST NIGERIA

“…It is speculated that the pest spread from its native America to Africa as contaminants of agricultural produce or by flying wind-aided Assefa & Ayalew 2019;Kasoma et al, 2020). Though S. frugiperda moths can undertake wind-assisted travels over several hundred kilometers at heights of several hundred metres (Westbrook et al, 2016;Zhou et al, 2020), no evidence exists of the species ability to travel wind-assisted over very long distances. Nevertheless, whether as contaminants or as a stowaway, it is evident that the ability of unfed S. frugiperda moths to survive for up to seven days, as shown in the present study, enhanced its spread to and from the African continent.…”