An insect survey was completed on 26 lines of hybrid poplar (Populus nigra x P. maximowiczii) that had the Roundup® Ready and Bt (Bacillus thuringiensis) genes. The survey was conducted in Kentucky in cooperation with MeadWestvaco. A total of 260 trees were evaluated. Survival rate averaged 74.2 percent among the lines. Poplar borer [Saperda calcarata (Say) Coleoptera: Cerambycidae] infested 22.2 percent of the trees. Other insects were present but to a lesser degree. Resistance to insect attack appeared evident in some lines but not in all. Experimental hybrid lines have not been approved for release, and this study adds to the information concerning herbivory on genetically modified material.
Stone, W. Doug; Beatty, T. Keith; Nebeker, T. Evan. 2006. Survey of twenty-six hybrid poplar lines for poplar borer. Gen. Tech. Rep. SRS-92. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. pp. 456-458