The life cycle functional response of Rhopalosiphum padi (L.) to higher temperature: territorial expansion of permanent parthenogenetic development as a result of warmer weather conditions

Bird cherry-oat aphid (Rhopalosiphum padi L.) is the most abundant aphid species on cereals in Poland. It represents approximately 80% of all cereal aphids. Its anholocyclic forms are the most important vectors of Barley yellow dwarf virus (BYDV). These forms are new among the Polish population of R. padi. Their changes in development are the result of higher temperatures. High spring and summer temperatures initiate a change in the run of R. padi’s life cycle, which begins to reproduce by means of permanent parthenogenesis. In autumn, this aphid does not fly back to the primary host but inhabits wild grasses. It is in autumn that winter cereals emerge. This results in what appears to be a new problem because this viral infection spreads in warmer environmental conditions.