Effect of Continuous Rearing in Rescue Wheat on Survival of the Wheat Stem Sawfly, Cephus cinctus Nort. (Hymenoptera: Cephidae)

Abstract

Rescue wheat has been grown in the prairie regions of Canada and the United States since 1946 as a control for the wheat stem sawfly, Cephus cinctus Nort. Although there is no evidence of the existence of a strain of sawflies to which Rescue is not resistant, the possibility of the development of such a strain is an important consideration. Callenbach (1952) found no differences in the percentages of Rescue sterns cut by the progenies of sawflies reared the previous year in Rescue and in susceptible varieties of wheat.The present work was done to determine whether a strain that would survive readily in Rescue wheat could be segregated by rearing sawflies continuously in this variety.