AGRO 3503.  Unit II-3.  Corn pest control.

Reference:  Corn Production Handbook


1. The most significant soil borne insect pest of corn are the seed corn maggot, S. corn

    rootworm, white grubs and:

            A. chinch bugs                                           B. nematodes

            C. slugs                                                            D. wireworms


2. The most destructive insect pest of later season field corn in Arkansas is:

            A. grasshoppers                                        B. corn borer complex

            C. fall leaf hoppers                                          D. chinch bugs


3. Controlling chinch bugs without the use of insecticides can be enhanced by:

            A. using a resistant variety                          B. chopping stalks

            C. planting early                                        D. planting late


4. Which of these foliar insecticides controls the broadest spectrum of insect pests?

            A. Gaucho                                                            B. Warrior T

            C. Sevin                                                    D. Asana


5. Corn hybrids with the Bt gene are NOT effective against:

            A. European corn borers                          B. grasshoppers

            C. SW corn borers                                           D. corn ear worms


6. Stalk destruction following harvest helps control the SW corn borer because:

            A. it makes larvae more susceptible to temperature and rainfall

            B. it removes their primary food source

            C. it allows for better incorporation of post-harvest insecticides

            D. it has no effect on SW corn borer control


7. The best insecticide for fall armyworm control is:

            A. Sevin                                                    B. Asana

            C. Gaucho                                                        D. foliar insecticides are not effective


8. Anthracnose disease is favored by:

            A. high soil N                                                   B. wet, warm weather

            C. dry, hot weather                                                D. cool, wet weather


9. Common smut disease is favored by:

            A. high soil N                                                   B. wet, warm weather

            C. dry, hot weather                                                D. cool, wet weather


10. Aflatoxin is produced by:

            A. Aspergillis flavus                                        B. Cercospora zeae

            C. Collefotrichum graminicola                   D. Fusarium solanii


11. List below four ideas for reducing aflatoxin contamination in corn:







12. Stunted corn plants exhibiting chlorosis and stubby roots are most likely infected by:

            A. nematodes                                                   B. root smut

            C. maize dwarf mosaic virus                              D. corn leaf blight


13. It is critical to have corn growing well and without stress for the first 9 weeks because:

            A. the root system is being established

            B. the leaf number and size is being established

            C. the ear size is being determined

            D. weeds attract more early season insect pests


14. Potential late season weed pests of corn in Arkansas are:

            A. barnyardgrass and crabgrass               B. crabgrass and goosegrass

            C. foxtail and broadleaf signalgrass                 D. pigweed and morningglory species


15. The herbicide that is the basis of most weed control programs in corn is:

            A. 2,4-D                                                          B. Roundup

            C. atrazine                                                        D. Dual


16. Which of these preemergence herbicide mixes provides the best weed control?

            A. atrazine + Lasso                                       B. Lasso + Beacon

            C. glyphosate and 2,4-D                                D. Lightning and Accent


17. Which of these is the most effective herbicide for nutsedge control in corn?

            A. 2,4-D                                                          B. atrazine

            C. Dual                                                            D. Permit


18. ‘Lightning’ herbicide is for use only:

            A. with ‘Roundup Ready’ herbicide                      B. only with ‘Bt’ varieties 

            B. only with ‘Clearfield’ varieties                  D. when following corn with rice


19. Which of these weeds has been shown to have biotypes in the mid-west with atrazine


            A. cocklebur                                                    B. johnsongrass

            C. pitted morningglory                             D. pigweed