The genetic control of flight activity in agricultural pest moths

Many of the most serious crop pests are moths, the caterpillars of which cause direct feeding damage. Chemical control often fails due to high levels of insecticide resistance, leading to billions of dollars in crop losses. The problems associated with pest control are exacerbated by high migratory activity of many species. While much progress has been made in understanding the biochemical and genomic factors controlling the development of insecticide resistance, we know comparatively little about the genetic factors controlling migratory flight.

Project Aim: This project will investigate individual variation in flight performance and activity in 2 species of British pest moths, and associate this individual variation with levels of expression of candidate genes associated with migratory activity. The studentship will focus on two common agricultural pests: the highly migratory Silver Y (Autographa gamma) and the partially migratory Large Yellow Underwing (Noctua pronuba).

Experimental Approaches: The project will take advantage of Rothamsted’s unique resources for studying insect flight. Individual variation in flight performance will be quantified under controlled laboratory conditions using our patented 48-channel rotational flight mills, which automatically record flight speed, duration, distance, and activity patterns of 48 individuals simultaneously over a night’s flight. The results from tethered flight under laboratory conditions will be validated by flying the same individuals in the field, using our unique harmonic radar system, which accurately records the flight-paths of tagged individuals over a range of several kilometres. Individuals from the lower and upper ranges of the flight performance spectra will be selected for molecular characterisation. The transcriptomes of these two species will be sequenced, de novo assembled and annotated following our established pipeline. The orthologs of candidate genes which have been previously associated with high levels of flight activity in another pest moth (Helicoverpa armigera) by a postdoc (Jones) working in our lab, and in the monarch butterfly, will be identified in both study species; and quantitative PCR used to investigate their expression levels in a range of individuals that show differences in flight performance. This approach will identify genes associated with increased flight activity across a range of migratory insects.

Project Rotations: Rotation 1 will involve characterising the migratory phenotype of the 2 species using the flight mills at Rothamsted. Rotation 2 will focus on genomic resequencing of migratory and non-migratory moths, or races of moth, to look for patterns of selection surrounding the genes identified by the micro-array at Rothamsted.