D3414: Chromosome-level genome assembly of Helicoverpa assulta (Lepidoptera: Noctuidae) provides an insight on the biology of the host-plant specialist

Helicoverpa assulta, commonly known as the oriental tobacco budworm, is a major agricultural pest in many parts of Asia. The larvae feed on only a few plants of Solanaceae family, causing significant damage to the crops such as hot pepper and tobacco. While the genomes of two congeneric generalist pests, H. armigera and H. zea, are available in public domains, no genome assembly of the specialist, i.e. H. assulta, has yet been reported. Here we present the chromosome-level genome assembly of a Korean strain of H. assulta (Pyeongchang strain, K18), which was obtained using a combination of the Nanopore long-read (ca. 78X) and Illumina NovaSeq short-read (ca. 54X) sequencings. The total assembly spans 424.36 Mb with an N50 length of 14.54 Mb and 35.44% GC contents. The final assembly (424.36Mb) consists of 62 scaffolds, of which the largest 31 scaffolds account for 98.7% of the assembly, confirming to the expected number of chromosomes (n = 31). Complete BUSCOs values were 99.0% and Repeat contents were 33.01%. Based on this assembly, genome annotation predicted 18,593 protein-coding genes. In addition to the host range difference, H. assulta acquire insecticide resistance at a much lower rate than H. armigera when exposed to the same insecticide. The pheromonal communication of H. assulta is also unique among other Heliothine moths. This genome of H. assaulta will shed light on various aspects of this specialist pest, including xenobiotic detoxification, insecticide resistance, host-plant interactions, and chemical communications, from the light of evolutionary relationship with other Helicoverpa generalists.