Apple aphid

Host plants: Apple, pear quince and other members of the family Rosaceae.

Morphology: The body of the apterous female is light to dark green, the antennae are yellow and the cauda and siphunculi are dark green to black.Alate females are mostly black, with a greenish abdomen; otherwise they are similar to the apterae. The length of the female body is 1.5-2.2 mm.

Life cycle: The aphids usually live on the same host throughout the year (autoecious), overwintering as eggs placed on apple branches. In the spring the emerging aphids reproduce by parthenogenesis till autumn, when males and sexual females appear and mate. The threshold of development is around 6ºC; at 16-20ºC a generation requires about 12 days, and each female has a average of 70 progeny. Summer irrigation, which promotes apple growth, also encourages increases in the aphids’ populations. Prior infestations by the pear lace bug, the tingid Stephanitis pyri (Fabricius), hinder the settlement of A. pomi.