Biochemical-manipulation
Guides
Tetraneura
elm-grass root aphids, woolly elm aphids
Tetraneura is a genus of gall-forming aphids in the family Aphididae, comprising more than 30 described species. These aphids are heteroecious, alternating between primary hosts in the genus Ulmus (elms), where they induce characteristic galls on leaves, and secondary hosts in the family Poaceae (grasses), where they feed on roots. The genus is notable for complex host manipulation, with species capable of altering host plant biochemistry to create nutritional sinks within galls. Several species, including the alien T. nigriabdominalis, are expanding their ranges in Europe and pose potential threats to cereal crops such as maize.