Host Preferences and Reproduction of Four Cereal Aphids on 20 Triticale Cultivars1

Abstract

The ability of cereal aphids to survive and reproduce on triticale (X Triticolsecale Wittmack) may be important in predicting yield losses caused by these aphids and the plant viruses they can vector. Since little specific information about aphid adaptation to triticale has been published, we have investigated the host relationships of four cereal aphid species and 20 triticale strains. Preferences and reproduction of Schizaphis graminum (Rondani), Macrosiphum avenae (F.), Rhopalosiphum padi (L.), and R. maidis (Fitch) were tested in environmental chambers on seedlings and mature stages of 20 strains of triticale. M. avenae reproduced equally well (P>0.05) on all strains in both growth stages but S. graminum reproduced more on seedling than on mature plants R. padi failed to reproduce on mature triticale and R. maidis was poorly adapted to both growth stages. There was no immunity among the strains, however, in some tests the strains could be ranked in groups (P<0.05) based on declining aphid responses. We concluded that S. graminum, M. avenae, and R. padi have the potential for causing significant yield losses in triticale, especially because of reproduction on seedling plants.