Importance of prezygotic isolation barriers between the two host strains of Spodoptera frugiperda

HÄNNIGER S.; UNBEHEND M. ; JUÁREZ M. L. ; SCHÖFL, G.; GROOT ASTRID T.; HECKE D. G.

Congreso; Scientific Advisory Board meeting 2012; 2012

The fall armyworm Spodoptera frugiperda(Lepidoptera: Noctuidae) is a serious pest species of a variety of crops throughout North and South America. This noctuid moth is an ideal model organism to study the process of sympatric speciation as well as the evolution of reproductive isolation, since two morphologically identical but genetically& behaviourally different ?host-strains? have been identified: the corn-strain that occurs on larger grasses such as corn and sorghum and the rice-strain inhabiting smaller grasses as rice and bermudagrass. So far three possible isolation barriers have been described between the two strains: 1. behavioural isolation through differential timing of reproduction in the scotophase, 2. behavioural isolation in terms of different female sex pheromones and 3. habitat isolation through differential choice of host plants. The aim of our research is to disentangle the importance of all prezygotic isolation barriers and to evaluate their effect on assortative mating between both strains.