However, corn leaf aphids are capable of increasing their numbers dramatically. We still have heard very little in the way of significant numbers of first-generation European corn borers in 2000. For the most part, the first generation of the European corn borer will come to an end soon in southern Illinois. Recent mild winters have allowed the southwestern corn borer to thrive in our southern counties, and it has caused far more concern than the European corn borer. Numbers of southwestern corn borers this year are fairly large in some areas.
Entomologists debate whether first-generation southwestern corn borers cause economic damage.
But regardless of your take on this issue, the second generation of this important insect pest is worth your attention if you live or work south of I-70. In the study, they looked at the virus symptom development and how well the virus replicated in the plant for each virus singly and in combination. Most of our currently grown hybrids do not have susceptibility to the virus, but some inbreds do. And the study showed that the virus replicated well in the tissue despite the absence of lethal symptoms. Two things could happen.