The discrimination of Acanthoscelides aureolus Horn (Coleoptera: Bruch
idae) among individuals of its host plants, Astragalus kentrophyta var
. implexus (Fabaceae), was investigated using a path analytical model
that included seven demographic variables. Seed number proved to be th
e plant trait that contributed most to the rate bruchid use among host
individuals. Seed number also exerted an important indirect effect on
the correlations between the rate of bruchid use and the other variab
les in this analysis.