The Nutritional Ecology ofDectes texanus(Coleoptera: Cerambycidae): Does Host Choice Affect the Macronutrient Levels in Overwintering Larvae?

Abstract

Abstract Dectes texanus LeConte (Coleoptera: Cerambycidae) is a stem-boring cerambycid that is an agricultural pest of soybean and cultivated sunflower. For D. texanus, cultivated sunflower is thought to be nutritionally superior to soybean and preferred over soybean. This study compared the macronutrient levels in overwintering larvae and the pith of the host plants to determine if soybean is an inferior host. The levels of total protein, total carbohydrates, and total lipids were measured in larvae from sunflower and soybean; larval head capsule width and larval mass also were compared. There were no differences between levels of total protein and total carbohydrates per unit mass between larvae from the 2 hosts; however, larvae from sunflower had significantly higher levels of lipids than larvae from soybean. A comparison of head capsule width indicated that larvae from soybean had significantly larger head capsule widths than those from sunflower, suggesting that soybean-fed larvae were larger or were...