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

Aphids of the genus Diuraphis caught by Johnson suction trap in Poznań, Poland

In 1973-2011 in Poznań, aphid catches were carried out using Johnson’s suction trap. Since then the suction trap located at the Institute of Plant Protection - National Research Institute in Poznań has continuously recorded the daily and seasonal dynamics of aphid flights. The collected results has been used to establish one of the largest databases of this type in Europe. The data also allow tracking changes in aphid biodiversity under the changing climatic conditions. Three aphid species of Diuraphis spp. were identified: D. muehlei (Börner, 1950) - in 1974, D. bromicola (Hille Ris Lambers, 1959) - in 1988, D. noxia (Kurdjumov, 1913) - in 2003 as a result of systematic and long-term aphid collections. The occurrence of D. noxia presents a particular risk to cereal crops in Poland. This expansive aphid species that originates from Asia and the Mediterranean is a vector of Barley yellow dwarf viruses (BYDV), and has become one of the most important pest of wheat and barley in the world. Changes in climatic conditions that have been observed in recent years in Poland such as hot summer, long and warm autumn, mild winter seem to be optimal for occurrence and development of aphid species from warmer parts of Europe