Technical Abstract: In the central and northern Plains, cultivated sunflower (Helianthus annuus L.) is attacked by a number of insect pests resulting in yield losses for sunflower producers. Host-plant resistance can provide a long-term solution to managing these insects with reduced input costs and with potentially lower environmental impact. Plant resistance is an integrated pest management tactic that utilizes the plant's own defenses to reduce damage caused by insect pests. In 2008, selected sunflower accessions, interspecific crosses, and sunflower lines were evaluated in field nurseries at Colby, KS, for lower densities of sunflower stem weevil, Cylindrocopturus adspersus (LeConte), larvae in stalks and at Highmore, SD, for reduced seed damage from larval feeding by the red sunflower seed weevil, Smicronyx fulvus LeConte. A number of S1 line progeny rows also were evaluated for these insects at the same locations. In addition to the recurrent selection program, a number of new populations (F2:3 lines) from insect-tolerant germplasm also were tested. In 2009, a separate study evaluated commercial hybrids at Mapleton, ND, for tolerance to the sunflower midge, Contarinia schulzi Gagne. Results from 2008 identified lines screened against the two insects with greatly reduced damage levels among the germplasm tested. There was a difference in seed damage of over 90% between the most susceptible and the most resistant line in the red sunflower seed weevil and 80% fewer larvae per stalk in the stem weevil trials. Results from the past several years, including 2009, have shown that commercially available sunflower hybrids vary in their midge reaction. Results from these evaluation trials enable producers to make informed decisions when choosing hybrids to grow in locations where a midge infestation has historically been a problem.