Sitobion avenae (F.)
Figure 7.10 Adult English grain aphid and nymphs.
Identification / Life Cycle
English grain aphid varities from yellowish-green to reddish-brown with long black legs and cornicles (Figure 7.10). They are larger than greenbugs, and their antennae are slightly longer than half the length of the body.
Plant Damage and Response
These aphids colonize wheat in the fall and feed on the leaves, causing no discernable damage. In spring, they feed in the heads where they can cause some kernels to shrivel. They are also vectors of barley yellow dwarf virus.
Management
Populations are normally held in check by various biological controls, and chemical treatments are rarely, if ever, justified. These aphids cause no discernable damage to wheat. The only management practice impacting English grain aphids would be one in which it was desirable to limit the spread of barley yellow dwarf virus.