Finding the genetic basis of prezygotic isolation barriers in the moth Spodoptera frugiperda

• Applicant: Professorin Dr. Astrid T. Groot
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology)
• Term: from 2009 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 155608721

The genetic basis of prezygotic isolation barriers is very poorly understood. The noctuid moth Spodoptera frugiperda (Fall armyworm), a pest species occurring sympatrically in the Americas, consists of two host strains, a corn and a rice strain. In this species three prezygotic isolation barriers are found: a) habitat isolation through host plant preference, b) behavioral isolation through differences in sex pheromone composition, and c) behavioral isolation through differential timing of mating activity at night. This proposal aims to find the genetic basis of these three prezygotic isolation barriers. By crossing and backcrossing strains of these two host races, we will conduct quantitative trait locus (QTL) analysis to assess prezygotic traits and location of genes. By phenotyping all traits in the same backcrosses, this project will have a unique opportunity to determine whether the same or different genomic regions underly the different prezygotic isolation barriers. The relative importance of the main QTL of each trait will be assessed experimentally by introgressing the major loci into separate homogeneous genetic backgrounds, and scoring all phenotypic assays with these separate lines. In this way, the effect of each QTL can be specifically measured and possible pleiotropic effects and/or epistatic interactions can be detected. The biological significance and variation of determined prezygotic differences found in the laboratory will be tested in the field at two different sites. (1519).

• DFG Programme: Research Grants