Corn Stalk Penetration Resistance as a Predictor of Southwestern Corn Borer (Lepidoptera: Crambidae) Survival

Studies were conducted to determine if corn stalk strength had an effect on southwestern corn borer (Diatraea grandiosella Dyar) survival during different growth stages. In 2006 southwestern corn borer larvae were placed on corn plants during dough stage near the ear and base of the plant. Penetration resistance was lower and borer survival was higher near the ear than near the base of the plant. In 2007, five corn hybrids were planted at three locations in Mississippi. Plants were infested with five 3rd instars at the ear zone during tassel, dough, and dent stages. Survival decreased as the corn progressed from tassel to dent stage. Survival varied among corn hybrids. The relationship between stalk strength and borer survival was not consistent, indicating that there are likely factors more directly limiting borer survival than physical stalk strength.