Preliminary host range assessment for the red sunflower seed weevil

Currently, management of the primary pest of cultivated sunflower, the red sunflower seed weevil (RSSW), Smicronyx fulvus (Col.: Curculionidae), rests almost entirely on insecticides. Alternative control methods include tillage, early planting, and host plant resistance. Wild Helianthus may be a source of such resistance. Unfortunately, descriptions of the RSSW host range are inadequate for this purpose. Thus, seven species of wild Helianthus (annuus, anomalus, argophyllus, debilis, niveus, praecox, and tuberosus) were assessed for RSSW larval development. This assessment was accomplished by placing blooming plants in an area with a high RSSW presence. After this, heads were brought to the lab, larvae were allowed to exit the head, and their masses were taken.