Sitobion akebiae is a promising alternative host aphid using a banker-plant system of Aphidius gifuensis. This study was conducted to evaluate the effect of host plant species and varieties on population growth of S. akebiae. Barley, wheat, oats and rye were tested in this study. The population increase of S. akebiae were lower on seedlings of the barley variety 'Shunrai' than other plants. But S. akebiae successfully increased on the matured plants with ears of 'Shunrai'. These results suggest that young seedlings of the barley 'Shunrai' should be useless for host plants of S. akebiae.
