Ultrastructural changes and transcriptional responses to resistant wheat and starvation in the midgut of Hessian fly larvae

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), is an important economic pest of wheat in all the major wheat growing regions of the United States. Virulent genotypes of Hessian fly pose a continuing threat to wheat production due to their ability to overcome genetic resistance. Thus, there is a need to better understand the precise mechanisms by which resistant plants are able to prevail over larval attack. Toxins produced by resistant plants may damage the midgut leading to larval starvation and death. In the present study, we describe ultrastructural differences observed in midguts of larvae residing on resistant versus susceptible wheat compared to larvae experiencing starvation while removed from a plant. Transcriptional responses of genes expressed in larval midguts under these conditions are also referenced.