Macrosiphum granarium , Siphonophora cerealis Insecta , Homoptera , Aphididae . Morphologically similar to apterae. However, development on the primary host has been abandoned in most cases and this species can be considered to be autoecious and restricted to the Gramineae . In autumn, some individuals become sexuparae , giving birth to sexuales.
Females lay eggs in the winter.
During mild winters, this species survives parthenogenetically on new growth of winter cereals and other Gramineae . Heavy infestations can cause a reduction of the number of grains per ears and thus a noticeable reduction of the yield. Sooty moulds develop on the honeydew which they secrete. Colony on ear of bearded wheat Winged individuals, nymphs and honeydew. .