Transcriptome analysis of fall armyworm Spodoptera frugiperda feeding on maize and sorghum

To investigate the adaptation mechanism of the fall armyworm Spodoptera frugiperda to different host plants at the transcriptional level.

This study carried out transcriptome sequencing, functional annotation and classification, as well as the analysis and verification of differentially expressed genes (DEGs) in larvae feeding on maize and sorghum.

Transcriptomic analysis identified 1454 DEGs in larvae feeding on sorghum relative to maize, including 860 upregulated genes and 594 downregulated genes. GO functional and KEGG pathway enrichment analyses showed that these DEGs were simultaneously enriched in processes related to carbohydrate and toxin metabolism, and so on. Among the DEGs, 39 DEGs were identified as detoxification enzyme genes, including 9 UDP-glucuronosyltransferase, 8 glutathione S-transferase, 3 carboxyl/cholinesterase, 16 cytochrome P450, and 3 ATP-binding cassette transporter genes. qRT-PCR validation further confirmed that sorghum feeding dramatically induced the expression of detoxification enzyme genes UGT2-4, UGT33B13, GSTS1, CYP4G74, and CYP4G15-2 in S. frugiperda larvae.

Collectively, this study, supported by both transcriptomic analysis and molecular validation, suggests that these upregulated detoxification enzyme genes play an essential role in the adaptation of fall armyworm larvae to sorghum as a host.