The insidious flower bug, Orius insidiosus, is known to feed on
the eggs of both European corn borer and corn earworm on corn. The searching behavior of this
predatory bug on reproductive stage field corn was studied. Corn borer eggs were placed on
upper or lower surfaces of leaves near the ear or on the ear husk to mimic the range of normal
placement of eggs. Orius adults were more likely to find eggs on the leaf surface than on the ear,
but were equally likely to find eggs on either the upper or lower surface of leaves. About 75corn
earworm eggs were placed on silks, tassels or leaves of each plant. The eggs most frequently fed
upon by Orius were those attached to the silks. As predator densities were increased from 1 to 12
Orius per plant, the percentage of eggs killed increased from 24% to 100%. Eggs placed on
tassels were rarely fed upon even at 12 Orius per plant, and eggs placed on leaves were only fed
upon at the highest predator rate (12 per plant), suggesting that these sites are much less
preferred. Orius bugs are highly attracted to corn silks which makes them a good predator of corn
earworm eggs, because corn earworm eggs are primarily laid in the silks. Although silks are
preferred by Orius, in the absence of prey in the silks, Orius were able to search for and kill
European corn borer eggs on both the upper and lower surfaces of leaves. These data suggest that
Orius insidiosus is well suited as a predator of corn earworm and European corn borer eggs on
reproductive stage field corn.
Source: Reid, C. R. 1991. Ability of
Orius insidiosus to search for, find, and attack European corn borer and corn
earworm eggs on corn. J. Econ. Entomol. 84: 83-86.
