Crop and Prairie Grasses Serving as Hosts for the Hessian Fly

Abstract

Insect herbivores typically parasitize a relatively small number of plant species. Host specialization is presumed to be a result of evolutionary arms races, with insect adaptations ultimately restricting host range. Being a gall-maker, the Hessian fly has highly evolved interactions with plant hosts. As a consequence, its host range is expected to be narrow. Two crop species, wheat and barley are hosts of the Hessian fly. I studied whether non-crop grasses can also serve as hosts. Included in tests were seven grass species that are important components of the grasslands of the Northern Great Plains. Although less suitable than wheat and barley, all seven species received eggs and five of the seven species supported development of offspring to the adult reproductive stage. Results indicate a broader host range than was expected. A benefit of being able to use non-crop grasses is availability of alternate hosts when superior crop hosts are not available.