Variation in sexual communication and its role in divergence of two host strains of the noctuid moth Spodoptera frugiperda

The main aim of my thesis was to investigate sexual communication differences between corn- and rice-strain individuals in order to assess whether strain-specific pheromonal communication acts as prezygotic mating barrier between the two S. frugiperda strains. Another aim was to distinguish strain-specific variation from geographic variation and to determine the genetic basis of female pheromone differences. Based on the strain-specific variation found in signal and response, the importance of sexual communication as a prezygotic isolation barrier is discussed and I propose how sexual communication differences may have evolved.