Trade-offs of host use between generalist and specialist Helicoverpa sibling species: adult oviposition and larval performance

摘要: Much attention has been paid to the question of relative importance female behaviour versus larval feeding capacities in determining host range herbivorous insects. Host-use trade-offs displayed by generalist and specialist sister species genus Helicoverpa were evaluated examine relationship between maternal choice offspring performance. The prediction optimal oviposition theory, that females will choose lay eggs on plants which their perform best as larvae, was tested measuring preference performance armigera H. assulta tobacco, sunflower, hot pepper. These two measures more highly correlated assulta. Both exhibited same ranking: tobacco > sunflower > hot larvae preferred followed tobacco pepper; while sunflower pepper, consistent with mothers’ preference. Duration total period from egg adult emergence for each significantly shorter plant larvae. had duration higher growth rate than vice versa indicating differences utilization. Thus, only predicted pattern, both show least worst. Selection may be stronger specialist, fewer choices lower lifetime fecundity generalist.