Responses of Resistant and Susceptible Wheats to Hessian Fly Attack¹

Abstract

Synopsis Hessian fly resistant wheats infested at first leaf stage, unlike susceptible wheats, undergo little stunting of subsequently developed leaves. Larvae migrated normally downward, but were constantly carried upward by the elongating second leaf. Four days after hatching, most larvae had died in the sheath column and were subsequently carried upward and above the enclosing leaf sheath. Normal growth of resistant leaves appears detrimental to larvae, but its relationship to the initial lethal effect is not understood.