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bioRxiv · 10.1101/2020.09.04.282533

The oriental fruit moth genome provides insights into evolutionary adaptation of tortricid pests

Abstract

Moths of the family Tortricidae (Insecta: Lepidoptera) usually distribute in temperate and tropical high upland regions. The oriental fruit moth (OFM) Grapholita molesta is a globally important pest of stone and pome fruit from this family. In this study, we assembled a chromosome-level genome for the OFM and conducted a comparative genomic analysis with other lepidopterans. This genome was assembled to 28 chromosomes with a size of 517.71 Mb, an N50 of 19.5 Mb, and a BUSCO completeness of 97.1%. In total, 19968 protein-coding genes were predicted, among which 15269 were functionally annotated. We manually annotated ten gene families for 13 representative genomes from the Lepidopteran. In general, two tortricid moths have a moderate number of detoxification and receptor genes and the lowest number of HSP genes, congruent with their polyphagous dietary and pattern of distribution. However, the OFM has the highest number of P450, I Rs and ORs among all species. Compared to the other tortricid species of the codling moth Cydia pomonella, the OFM has more genes in all gene families. Our results indicate that the high number of some detoxification and receptor genes may be related to the strong adaptation of OFM as a global pest. The high-quality genome of OFM provides an invaluable resource for understanding the ecology, genetics, and evolution of tortricid moths.

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Song, W., Cao, L.-J., Yue, L., Guo, S.-K., Chen, J.-C., Gong, Y.-J., Fan, X.-L., Wei, S.-J.. 2020-09-04. The oriental fruit moth genome provides insights into evolutionary adaptation of tortricid pests. https://doi.org/10.1101/2020.09.04.282533

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