The genome of the soybean gall midge (Resseliella maxima)

The cecidomyiid fly, soybean gall midge, Resseliella maxima Gagne, is a recently discovered insect that feeds on soybean plants in the Midwestern United States. R. maxima larvae feed on soybean stems that may induce plant death and can cause considerable yield losses, making it an important agricultural pest. From three pools of 50 adults each, we used long-read nanopore sequencing to assemble a R. maxima reference genome. The final genome assembly is 206 Mb with 64.88x coverage, consisting of 1,009 contigs with an N50 size of 714 kb. The assembly is high quality with a Benchmarking Universal Single-Copy Ortholog (BUSCO) score of 87.8%. Genome-wide GC level is 31.60%, and DNA methylation was measured at 1.07%. The R. maxima genome is comprised of 21.73% repetitive DNA, which is in line with other cecidomyiids. Protein prediction annotated 14,798 coding genes with 89.9% protein BUSCO score. Mitogenome analysis indicated that R. maxima assembly is a single circular contig of 15,301 bp and shares highest identity to the mitogenome of the Asian rice gall midge, Orseolia oryzae Wood-Mason. The R. maxima genome has one of the highest completeness levels for a cecidomyiid and will provide a resource for research focused on the biology, genetics, and evolution of cecidomyiids, as well as plant-insect interactions in this important agricultural pest.

Automated summary

The soybean gall midge, Resseliella maxima Gagne, is a recently discovered insect that feeds on soybean plants in the Midwestern United States and poses a significant threat to agricultural productivity. In this study, researchers used long-read nanopore sequencing to assemble a high-quality reference genome for R. maxima, providing valuable insights into its genetics and evolution. The genome analysis revealed the presence of repeating DNA sequences and identified coding genes and mitochondrial composition, which will contribute to further research on cecidomyiids and their interactions with plants.