As the brown marmorated stink bug (BMSB) becomes more well established around Ohio, its injury on sweet corn is becoming noticeable. In plantings that are sprayed frequently with pyrethroids such as Warrior or Hero for control of corn earworm, injury by stink bug is less likely to occur because pyrethroids are among the few insecticides that are toxic to stink bugs. But in plantings of transgenic sweet corn that do not need to be sprayed with insecticide for worm control, or in sweet corn that is sprayed by Coragen or Radiant for worm control, injury by stink bug is more likely to occur. Stink bugs feed by sucking juices from the kernels, after inserting their mouthparts through the husks (Figure 1). This results in kernels that are shrunken in a variety of ways, as shown in Figures 2 and 3 below. Both the adults (Figure 4) and the immature nymphs (Figure 5) feed on the kernels. The injury can occur anywhere on the ear; sometimes it is clustered near the tip, other times it is scattered along the entire length of the ear. In addition to sweet corn, BMSB has a wide range of host plants, ranging from raspberries, peaches, apples, and grapes to bell peppers, eggplant, green beans, swiss chard, and tomatoes.
-Celeste Welty, Extension Entomologist
Figure 1. Sweet corn ear being fed upon by adults and nymphs of the brown marmorated stink bug.
Figure 2. Sweet corn ear with many kernels injured by stink bug feeding.
Figure 3. Close-up view of kernels damaged by stink bug.
Figure 4. Adult of the brown marmorated stink bug.
Figure 5. Nymph of the brown marmorated stink bug.