Distribution and ecology of the Russian wheat aphid, Diuraphis noxia (Kurdj.), expanded to central Europe (Hom.: Aphididae)

A part of the territory of the Czech Republic represents the up-dated north ern limit of distribution (status 1997) which the Russian wheat aphid (= RW A), Diuraphis noxia (Kurdj.) has reached during its expansion from the sout heast to central Europe. The newly defined area is classified as one of the adventive routes which may be derived from the main expansion of RWA from its native home (central-western Asia) into the broader Mediterranean area. Distribution and its history, and ecology (life-cycle, host plants, season al history, both native and introduced natural enemies) of RWA are presente d on ground of field evidence and trials obtained in 1995-1997 in the Czech Republic. The origin of RWA, its distribution and establishment in the tar get area, as well as prognosis of its further expansion, are reviewed and d iscussed. Steps and approaches to RWA detection in the crop, as well as som e notes on its management, are added.