Cry Iab controls
A corn borer
B what rust
C cotton insects
D maize height insects
Answers
The Cry proteins / toxins are obtained from the bacterium Bacillus thuringiensis (Bt) and have its effect on insect orders Lepidoptera (moths and butterflies), Diptera (flies and mosquitoes), Coleoptera (beetles) and Hymenoptera ( wasps, bees, ants and saw flies). As borers belong to Lepidoptera so the right answer is A. corn borer.
An average of one European corn borer cavity per stalk across an entire field can reduce yield by as much as 5% by the first generation and 2.5% by the second generation.
How often is any particular field likely to have an average of one or more cavities per stalk at the end of the season? That is difficult to say. In general, corn borers have been under scouted and under treated in Kentucky.
Other states report annual losses to European corn borer to be approximately 5 to 10 percent annually. Information on the average number of cavities per stalk at the end of the season is not available for Kentucky