Transcriptomic analysis of the response of Spodoptera frugiperda (Lepidoptera: Noctuidae) to short-term low-temperature stress

Spodoptera frugiperda is a major invasive pest that poses a serious threat to crops worldwide. Low temperature is a key factor limiting the survival and reproduction for this pest. To study the responses of S. frugiperda to low-temperature stress, high-throughput sequencing was used to perform transcriptomic analysis on the 6^th instar larvae under low-temperature stress at 5 °C and 10 °C, along with 25 °C as a control. As a result, 215 differentially expressed genes (DEGs) were identified under different low-temperature stresses. Upon functional annotation of the DEGs in KEGG and GO databases, the number of DEGs annotated in control vs. LT10 comparison was the largest (n = 150), whereas fewer DEGs (n = 89) were annotated in control vs. LT5 comparison. This discrepancy suggested that S. frugiperda might adopt different strategies to cope with low-temperature stress. The DEGs in the GO database were particularly associated with cell catalytic activity, cell anatomical entity process, cell apoptosis, and cell binding channel. KEGG annotation analysis of the different low-temperature stresses showed that most of the enriched pathways were related to carbon metabolism, oxidative phosphorylation, and lipid metabolism. The results will be the basis for mastering the cold tolerant mechanism of S. frugiperda, and is of great significance for its prevention.