What kind of impact can corn leaf aphids have on the plant ?
In 1996, University of Illinois Extension entomologists, Kevin Steffey and Mike Gray, provided information through their newsletter that reported on a “quick-and-dirty” study from 1980 conducted to assess the impact aphids had on field corn yields. They tagged plants with no aphids, moderate numbers (100 or more but no leaves covered), and heavy numbers (tassel and the top 2 to 4 leaves with aphids). The plants were tagged after pollination was complete. The ears from tagged plants were hand harvested and kernel weight was determined. They found a significant decrease in kernel weight as the density of aphids increased. In their “high-management” plots, moderate infestations reduced kernel weight by 11%, heavy infestations by 37% when compared to non-infested plants. They also found more barren plants in the samples from heavily infested plots than in the moderately and non-infested plots. Corn leaf aphids cause the greatest injury to corn before pollination is completed. Results of a
