Influence of western corn rootworm (Coleoptera : Chrysomelidae) larval injury on yield of different types of maize

Two field experiments were conducted in 1995-1996 to determine if there are common yield responses among maize hybrids to larval western corn rootworm , Diabrotica virgifera virgifera LeConte injury. Three yellow dent hybrids, five white food grade dent hybrids, and a popcorn hybrid were included in the study. The minimum level of rootworm injury as measured by root damage ratings (3.2-4.2) that significantly reduced yield was similar across the h ybrids included in the study. However, the pattern of yield response to dif ferent rootworm injury levels varied among hybrids. This suggests that maiz e hybrids may inherently differ in their ability to tolerate rootworm injur y and partition biomass in response to injury and other stresses. The compl ex interaction among hybrid, level of injury, and other stresses suggests t hat a common western corn rootworm injury-yield relationship may not exist within maize.