Specialization and host plant use of the common clones of Sitobion avenae (Homoptera: Aphididae)

The performance of 10 clones of the grain aphid Sitobion avenae Fabricius was measured over three generations on three host plants (wheat, bluegrass and ryegrass). The tested clones belonged to six microsatellite genotypes; two genotypes were represented by three clonal lines each that had been collected from different host plants. The clones varied in body color and in the secondary endosymbionts they possessed (Hamiltonella, Regiella or none). The performance of aphids on host plants declined in the order wheat > bluegrass > ryegrass independently of the plant from which they were collected. We also found differences in performance among genotypes and clones of the aphids and among the generations at which the performance was measured. The performance was not affected by the collection site, clone's original host plant, body color or the presence of endosymbionts.