Transcriptome Analysis of the Larch Bud Gall Midge, Dasineura rozhkovi Mamaev et Nikolskij: De Novo Assembly, Phylogeny and Sexual Dimorphism

The larch bud gall midge (Dasineura rozhkovi Mamaev et Nikolskij) is one of the main pests infesting larches. Its activity causes developmental defects and a noticeable decrease in population growth in adult Siberian larches (Larix sibirica Ledeb.). Due to its complex life cycle and active presence in areas of human habitation, this insect is difficult to exterminate using common methods. D. rozhkovi has not been studied before with the use of sequencing technologies, which means there is no information on the mechanisms occurring in its body at the molecular level. Here, we present for the first time a de novo assembly and analysis of the D. rozhkovi transcriptome. We found a pronounced sexual dimorphism in differential gene expression in D. rozhkovi imagoes and performed a phylogenetic analysis using earlier-published genome assemblies of the insects belonging to several large clades. The resulting phylogenetic tree includes D. rozhkovi and eight other gall midge species and shows the closest relationship between D. rozhkovi and the Hessian fly (Mayetiola destructor Say). We believe that the obtained results can be further used for developing measures to control this pest.