Interference of cocklebur weevil with Dectes development in sunflowers may have a positive impact on soybeans

The soybean stem borer Dectes texanus LeConte (Coleoptera: Cerambycidae) is a native long-horned beetle that feeds typically on soybeans and sunflowers, while the cocklebur weevil Rhodobaenus quinquepunctatus Say (Coleoptera: Curculionidae) colonizes stems of sunflower and other weeds but soybeans. Here we report a previously unknown interaction between these two insects that may be restricting the success of Dectes larvae in sunflowers and discuss the use of sunflowers as trap crops in soybean fields.